U C Version: 3.0 beta - June 25, 2015 Contents Introduction About . . . . . . . . . . . Disclaimer . . . . . . . . . Software disclaimer . Limitation of liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5 6 6 6 Input General information . . . . . . . . . . . . . . Structure . . . . . . . . . . . . . . . . . Abbreviations . . . . . . . . . . . . . . Functions & parameters . . . . . . . . . Binary and ASCII output . . . . . . . . Input handling . . . . . . . . . . . . . . . . *END . . . . . . . . . . . . . . . . . . *INCLUDE . . . . . . . . . . . . . . . . *INCLUDE BINARY . . . . . . . . . . *UNIT SYSTEM . . . . . . . . . . . . Solution control and techniques . . . . . . . *ANALYSIS BUCKLING EIGENMODE *ANALYSIS DYNAMIC EIGENMODE . *ANALYSIS LINEAR STATIC . . . . . *GPU . . . . . . . . . . . . . . . . . . *SMS . . . . . . . . . . . . . . . . . . *SMS CLUSTER . . . . . . . . . . . . *TIME . . . . . . . . . . . . . . . . . . Output . . . . . . . . . . . . . . . . . . . . *OUTPUT . . . . . . . . . . . . . . . . *OUTPUT ELEMENT . . . . . . . . . *OUTPUT FORMING . . . . . . . . . . *OUTPUT NODE . . . . . . . . . . . . *OUTPUT SENSOR . . . . . . . . . . Mesh Commands . . . . . . . . . . . . . . . *ACTIVATE ELEMENTS . . . . . . . . *COMPONENT BOLT . . . . . . . . . *COMPONENT BOX . . . . . . . . . . *COMPONENT CYLINDER . . . . . . *COMPONENT PIPE . . . . . . . . . . *COMPONENT SPHERE . . . . . . . . *MERGE DUPLICATED NODES . . . . *REFINE . . . . . . . . . . . . . . . . . *SMOOTH MESH . . . . . . . . . . . *TRANSFORM MESH CARTESIAN . . *TRANSFORM MESH CYLINDRICAL . *TRIM . . . . . . . . . . . . . . . . . . *WELD . . . . . . . . . . . . . . . . . Nodes and connectivity . . . . . . . . . . . . *CHANGE P-ORDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7 7 7 8 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 IMPETUS Afea Solver v.3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 *ELEMENT CHEX . . . . . . . . . . . . . . *ELEMENT CPRISM . . . . . . . . . . . . . *ELEMENT CTET . . . . . . . . . . . . . . *ELEMENT QHEX . . . . . . . . . . . . . . *ELEMENT QPRISM . . . . . . . . . . . . . *ELEMENT QTET . . . . . . . . . . . . . . *ELEMENT SHELL . . . . . . . . . . . . . . *ELEMENT SOLID . . . . . . . . . . . . . . *NODE . . . . . . . . . . . . . . . . . . . . *PART . . . . . . . . . . . . . . . . . . . . . Material properties . . . . . . . . . . . . . . . . . *EOS GRUNEISEN . . . . . . . . . . . . . . *EOS POLYNOMIAL . . . . . . . . . . . . . *EOS TAIT . . . . . . . . . . . . . . . . . . *MAT CERAMIC . . . . . . . . . . . . . . . *MAT CREEP . . . . . . . . . . . . . . . . . *MAT ELASTIC . . . . . . . . . . . . . . . . *MAT FLUID . . . . . . . . . . . . . . . . . *MAT FOAM . . . . . . . . . . . . . . . . . *MAT FORMING . . . . . . . . . . . . . . . *MAT FORMING R . . . . . . . . . . . . . . *MAT GRANULAR CAP . . . . . . . . . . . *MAT HJC CONCRETE . . . . . . . . . . . *MAT JC . . . . . . . . . . . . . . . . . . . *MAT JC FIELD . . . . . . . . . . . . . . . *MAT JH CERAMIC . . . . . . . . . . . . . *MAT LIBRARY . . . . . . . . . . . . . . . *MAT METAL . . . . . . . . . . . . . . . . . *MAT MOONEY RIVLIN . . . . . . . . . . . *MAT MULTILAYER ORTHOTROPIC . . . *MAT ORTHOTROPIC . . . . . . . . . . . . *MAT PWL . . . . . . . . . . . . . . . . . . *MAT RIGID . . . . . . . . . . . . . . . . . *MAT USER JS . . . . . . . . . . . . . . . . *MAT USER X . . . . . . . . . . . . . . . . *MAT VISCO PLASTIC . . . . . . . . . . . *PROP DAMAGE BRITTLE . . . . . . . . . *PROP DAMAGE CL . . . . . . . . . . . . . *PROP DAMAGE CL ANISOTROPIC . . . . *PROP DAMAGE IMP . . . . . . . . . . . . *PROP DAMAGE IMP ISO . . . . . . . . . . *PROP DAMAGE JC . . . . . . . . . . . . . *PROP DAMAGE STRAIN . . . . . . . . . . *PROP THERMAL . . . . . . . . . . . . . . Initial conditions . . . . . . . . . . . . . . . . . . *INITIAL DAMAGE RANDOM . . . . . . . . *INITIAL DAMAGE SURFACE RANDOM . . *INITIAL MATERIAL DIRECTION . . . . . . *INITIAL MATERIAL DIRECTION VECTOR *INITIAL MATERIAL DIRECTION WRAP . IMPETUS Afea Solver v.3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 49 51 53 55 57 58 59 61 62 63 65 66 67 68 71 73 74 75 77 79 80 82 84 85 87 89 90 92 94 95 97 98 99 100 101 104 105 106 107 108 109 110 111 112 113 114 116 117 118 2 *INITIAL STATE . . . . . . . . . . *INITIAL STATE HAZ . . . . . . . *INITIAL STATE WELDSIM . . . . *INITIAL STRESS FUNCTION . . . *INITIAL TEMPERATURE . . . . . *INITIAL VELOCITY . . . . . . . . Boundary conditions . . . . . . . . . . . *BC MOTION . . . . . . . . . . . . *BC SYMMETRY . . . . . . . . . . *BC TEMPERATURE . . . . . . . . Loads . . . . . . . . . . . . . . . . . . . *LOAD CENTRIFUGAL . . . . . . . *LOAD DAMPING . . . . . . . . . *LOAD FORCE . . . . . . . . . . . *LOAD GRAVITY . . . . . . . . . . *LOAD PRESSURE . . . . . . . . . *LOAD SHEAR . . . . . . . . . . . *LOAD THERMAL BODY . . . . . *LOAD THERMAL SURFACE . . . *PRESTRESS BOLT . . . . . . . . Contact and tied interfaces . . . . . . . . *CONTACT . . . . . . . . . . . . . *MERGE . . . . . . . . . . . . . . . *MERGE FAILURE COHESIVE . . . *MERGE FAILURE FORCE . . . . . Rigid bodies . . . . . . . . . . . . . . . . *RIGID BODY DAMPING . . . . . *RIGID BODY INERTIA . . . . . . *RIGID BODY JOINT . . . . . . . *RIGID BODY MERGE . . . . . . . Connectors . . . . . . . . . . . . . . . . *CONNECTOR RIGID . . . . . . . *CONNECTOR SPR . . . . . . . . *CONNECTOR SPRING . . . . . . Parameters and functions . . . . . . . . *CURVE . . . . . . . . . . . . . . . *FUNCTION . . . . . . . . . . . . . *FUNCTION STATIC . . . . . . . . *PARAMETER . . . . . . . . . . . Geometries . . . . . . . . . . . . . . . . *GEOMETRY BOX . . . . . . . . . *GEOMETRY EFP . . . . . . . . . *GEOMETRY PART . . . . . . . . *GEOMETRY PIPE . . . . . . . . . *GEOMETRY SEED COORDINATE *GEOMETRY SEED NODE . . . . *GEOMETRY SPHERE . . . . . . . Sets . . . . . . . . . . . . . . . . . . . . *SET ELEMENT . . . . . . . . . . *SET FACE . . . . . . . . . . . . . IMPETUS Afea Solver v.3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 143 144 145 146 147 148 149 151 152 153 154 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 3 *SET GEOMETRY . . . . . . . . . . . . *SET NODE . . . . . . . . . . . . . . . . *SET PART . . . . . . . . . . . . . . . . Coordinate system . . . . . . . . . . . . . . . *COORDINATE SYSTEM CYLINDRICAL *COORDINATE SYSTEM FIXED . . . . *COORDINATE SYSTEM NODE . . . . Discrete Particles . . . . . . . . . . . . . . . . *PBLAST . . . . . . . . . . . . . . . . . *PSOIL . . . . . . . . . . . . . . . . . . Smoothed Particle Hydrodynamics . . . . . . . *SPH FLUID . . . . . . . . . . . . . . . *SPH SENSOR PRESSURE . . . . . . . *SPH WATER ENTRY LAB . . . . . . . IMPETUS Afea Solver v.3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 174 175 176 177 178 179 180 181 183 184 185 187 188 4 Introduc on About IMPETUS Afea Solver is a general non-linear finite element software used to predict the large deformation behavior of materials. Such deformations usually occur in components and structures when they are subjected to extreme loading conditions. IMPETUS Afea has the vision to provide the best simulation aided engineering competence. Our software is based on a selection of highly accurate and innovative algorithms. By utilizing new GPU hardware technology, users are able to achieve extremely accurate results with low hardware investments and high computational speed. Precision for decision is about being able to take the right decisions when evaluating your computational results, making IMPETUS Afea Solver a tool for decision making. The number of purely numerical parameters that the user has to provide as input has been kept to a minimum, with a clear focus on simplicity combined with accuracy and robustness. When the user defines the structural form, material properties and loading well, the software delivers precise results. The IMPETUS Afea Solver is not suited for all applications: some special cases requires a different modelling approach, however, for the problem classes of mechanical engineering for which the code has been developed, our tool is ideal. Further validation by comparing your numerical results with the corresponding experimental tests should always be part of engineering philosophy when using non-linear finite element tools. Live tests to establish confidence in your model can never be excluded, but can be reduced when working with the IMPETUS Afea Solver, thus saving you both time and money. Users of the IMPETUS Afea Solver come from many different markets: oil&gas, defence, aerospace, automotive amongst others. Despite the differing applications, we identify key similarities in the modelling challenges and develop new functionalities in the code. We continuously strive to innovate in order to improve the Solver, relishing your challenges. IMPETUS Afea Solver v.3.0 5 Disclaimer So ware disclaimer Software is provided ’as is’ without warranty of any kind, either express or implied, including, but not limited to, the implied warranties of fitness for a purpose, or the warranty of non-infringement. In no event shall IMPETUS Afea AS be liable for any special, punitive, incidental, indirect or consequential damages of any kind, or any damages whatsoever, including, without limitation, those resulting from loss of use, data or profits, whether or not IMPETUS Afea has been advised of the possibility of such damages, and on any theory of liability, arising out of or in connection with the use of this software. No advice or information, whether oral or written, obtained from IMPETUS Afea shall create any warranty for the software. Limita on of liability Under no circumstances shall IMPETUS Afea be liable for any losses or damages whatsoever, whether in contract, tort or otherwise, from the use of, or reliance on, the Materials. NEITHER IMPETUS AFEA NOR ANY OF ITS SUBSIDIARIES OR LICENSORS SHALL BE LIABLE FOR LOSS OF PROFITS, LOSS OR INACCURACY OF DATA, OR INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. NOTHING IN THIS LIMITATION OF LIABILITY SHALL LIMIT IMPETUS AFEA.S LIABILITY FOR DEATH OR PERSONAL INJURY CAUSED BY ITS NEGLIGENCE OR THE NEGLIGENCE OF ITS EMPLOYEES. For the purposes of this section, ”IMPETUS Afea” shall include IMPETUS Afea AS, and its divisions, subsidiaries, successors, parent companies, and their employees, partners, principals, agents and representatives, and any third-party providers or sources of Materials. IMPETUS Afea Solver v.3.0 6 Input General informa on Structure A model is built up by a series of commands. Example models can be downloaded from the Samples menu in our online manual. *COMMAND parameter1, parameter2, parameter3, ... Abbrevia ons For the input the following abbreviations can be used: Abbreviation E ES F FS G GS N NS P PS ALL A V D X Y Z IMPETUS Afea Solver v.3.0 Description element element set element face element face set geometry geometry set node node set part part set everything acceleration velocity displacement x-coordinate y-coordinate z-coordinate 7 Func ons & parameters The following built in functions and parameters are supported by the commands FUNCTION and PARAMETER. They can also be used when defining expressions replacing numerical values in the input deck. Function/parameter pi abs(x) erf(x) H(x) sign(x) min(x1, x2, ... xn) max(x1, x2, ... xn) sin(x) cos(x) exp(x) sqrt(x) smooth d(d max, t0, t1) smooth v(d max, t0, t1) smooth a(d max, t0, t1) mine dry(m,x,y,z,z0) ˆ IMPETUS Afea Solver v.3.0 Description 3.141592653589793.. absolute value classical error function step function (H(x < 0) = 0; H(x ≥ 0) = 1) sign function (sign(x < 0) = -1; sign(x ≥ 0) = 1) min function max function trigonometric sine function trigonometric cosine function exponential function (exp(x) = ex ) square root smooth displacement function going from 0 at time t0 to d max at t1 smooth velocity function that is obtained by differentiating smooth d with respect to time smooth acceleration function that is obtained by differentiating smooth v with respect to time pressure function that mimics a cylindical mine buried in dry soil (TNT equivalent mass m, height/diameter ratio 1/3, charge center coordinate at (x,y,z), ground level at z0 exponent (xˆy = xy ) 8 The following functions are only supported by the command FUNCTION. IMPETUS Afea Solver v.3.0 9 Function / parameter crv(cid,x) dist surf(xn,yn,zn) dmg dnorm dt epsp fxc(cid) fyc(cid) fzc(cid) fc(cid) fxr(bcid) fyr(bcid) fzr(bcid) fr(bcid) pres sigy0 t volfs vnorm vtang vx vy vz vxn(nid) vyn(nid) vzn(nid) vn(nid) vxp(pid) vyp(pid) vzp(pid) wip(pid) wkp(pid) x y z X Y Z xnorm ynorm znorm xn(nid) yn(nid) zn(nid) IMPETUS Afea Solver v.3.0 Description returns the ordinata of curve cid at abscissa x distance to material surface damage spring elongation current time step size effective plastic strain total contact force in x-direction in contact interface cid total contact force in y-direction in contact interface cid total contact force in z-direction in contact interface cid total contact force in contact interface cid reaction force in x-direction in *BC MOTION definition bcid reaction force in y-direction in *BC MOTION definition bcid reaction force in z-direction in *BC MOTION definition bcid total reaction force in *BC MOTION definition bcid contact pressure or hydrostatic pressure in material initial yield stress (can be unique for each integration point if using INITIAL STATE WELDSIM) current time volume enclosed by face set fsid local velocity in the normal direction to the surface of the structure relative tangential sliding velocity (for use with CONTACT) local velocity in x-direction (e.g. velocity of an element face in LOAD PRESSURE or a node in LOAD MOTION) local velocity in y-direction local velocity in z-direction velocity in x-direction of node nid velocity in y-direction of node nid velocity in z-direction of node nid velocity of node nid velocity in x-direction of part pid velocity in y-direction of part pid velocity in z-direction of part pid internal energy of part pid kinetic energy of part pid local x-coordinate (e.g. location of an element face in LOAD PRESSURE or a node in LOAD MOTION) local y-coordinate local z-coordinate initial x-coordinate (e.g. location of an element face in LOAD PRESSURE or a node in LOAD MOTION) initial y-coordinate initial z-coordinate x-component of local surface normal direction y-component of local surface normal direction z-component of local surface normal direction x-coordinate of node nid y-coordinate of node nid z-coordinate of node nid 10 Binary and ASCII output The solver outputs global simulation results in binary files with the extension .imp. A header file impetus.imp is created when the simulation begins and each frame that is being output is written to its own file (impetus 0000.imp, impetus 0001.imp. etc.). The output interval is specified in the command OUTPUT. The global output is complemented with a set of ASCII files having the extension .out. The data in the .imp and .out- files can be read and visualized by the IMPETUS Afea Post Processor. ASCII file contact.out dt.out element.out energy.out merge.out node.out part.out pblast.out pblast contact.out prescribed.out rigid.out sph contact.out spr.out spring.out Content Activated by command Forces, energies and maximum penetration for each contact interface Time step size information Stresses and plastic strain of a user defined set of elements Global energies Forces between merged interfaces Location, velocity and acceleration of a user defined set of nodes Masses (physical and mass scaling) and energies by part Discrete particle energy levels Impulses transferred from discrete particles to FE parts Reaction forces and moments on kinematically constrained surfaces and rigid bodies Displacements, velocities and forces acting on rigid bodies SPH-structure contact forces, energies and largest penetration SPR point connector forces, moments, deformations and damage Spring forces CONTACT IMPETUS Afea Solver v.3.0 Always active OUTPUT ELEMENT Always active MERGE OUTPUT NODE PART PBLAST PBLAST BC MOTION MAT RIGID SPH FLUID CONNECTOR SPR CONNECTOR SPRING 11 Input handling Input handling *END *INCLUDE *INCLUDE BINARY *UNIT SYSTEM IMPETUS Afea Solver v.3.0 12 Input handling *END *END Descrip on Defines the end of an input file. IMPETUS Afea Solver v.3.0 13 Input handling *INCLUDE *INCLUDE filename sfx , sfy , sfz , nid offset, eid offset, pid offset x 0 , y0 , z 0 , x 1 , y1 , z 1 x ¯x , x ¯y , x ¯z , y¯x , y¯y , y¯z Parameter defini on Variable Description filename sfx , sfy , sfz The path and the name of file to be included Scale factors for nodal coordinates in x, y and z directions default: 1 Number to add to all node ids Number to add to all element ids Number to add to all part ids Start point for mesh translation End point for mesh translation New direction of x-axis default: (1,0,0) New direction of y-axis default: (0,1,0) nid offset eid offset pid offset x0 , y0 , z0 x1 , y1 , z1 x ¯x , x ¯y , x ¯z y¯x , y¯y , y¯z Descrip on This command is used to merge a file with the input. The data in the included file can be transformed (optional). A point in the original configuration x will be moved to location x0 according to: x ¯x y¯x z¯x sfx (x − x0 ) ¯y y¯y z¯y · sfy x0 = x1 + x x ¯z y¯z z¯z sfz Hence, a point x0 in the original configuration will be moved to x1 . This is the base point for both scaling operations and rotations. IMPETUS Afea Solver v.3.0 14 Input handling *INCLUDE BINARY *INCLUDE BINARY filename Parameter defini on Variable Description filename The path and the name of binary file to be included Descrip on This command is used to merge a binary file with the input. IMPETUS Afea Solver v.3.0 15 Input handling *UNIT SYSTEM *UNIT SYSTEM units Parameter defini on Variable Description units Unit system options: SI → [m, kg, s] MMTONS → [mm, ton, s] CMGUS → [cm, g, µs] IPS → [in, slinch, s] MMKGMS → [mm, kg, ms] Descrip on Command to inform the solver of used unit system. A unit system must be specified if the PBLAST command is used. Specifying a unit system also facilitates the scanning for suspected errors in the input deck. Possible errors or mistakes are reported in the ASCII file ”impetus.attention”. IMPETUS Afea Solver v.3.0 16 Solu on control and techniques Solu on control and techniques *ANALYSIS BUCKLING EIGENMODE *ANALYSIS DYNAMIC EIGENMODE *ANALYSIS LINEAR STATIC *GPU *SMS *SMS CLUSTER *TIME IMPETUS Afea Solver v.3.0 17 Solu on control and techniques *ANALYSIS BUCKLING EIGENMODE *ANALYSIS BUCKLING EIGENMODE N, psid σstif f Parameter defini on Variable Description N psid Number of computed eigenmodes ID of part set that is included in the linear solution default: complete model is active Stress stiffening activation flag options: 0 → buckling due to external loads (default) 1 → buckling due to scaling of initial stress field σstif f Descrip on This command is used to activate and to define settings for a dynamic eigenmode analysis. IMPETUS Afea Solver v.3.0 18 Solu on control and techniques *ANALYSIS DYNAMIC EIGENMODE *ANALYSIS DYNAMIC EIGENMODE N, psid σstif f Parameter defini on Variable Description N psid Number of computed eigenmodes ID of part set that is included in the eigenmode analysis default: complete model is active Stress stiffening activation flag options: 0 → not active 1 → active from applied external loads 2 → active from initial stresses σstif f Descrip on This command is used to activate and to define settings for a dynamic eigenmode analysis. IMPETUS Afea Solver v.3.0 19 Solu on control and techniques *ANALYSIS LINEAR STATIC *ANALYSIS LINEAR STATIC solver, psid, when typesub , Nsub , σstif f Parameter defini on Variable Description solver Solution technique options: 0 → direct 1 → iterative (conjugate gradient) ID of a part set listing parts that are included in the linear solution default: complete model is active Flag indicating when to carry out the linear static analysis options: 0 → at time = 0 1 → at termination time Sub-structuring method options: 0 → no sub-structuring 1 → based on free bodies 2 → direction based Number of sub-structures (only used if typesub =2) Stress stiffening activation flag options: 0 → not active 1 → active psid when typesub Nsub σstif f Descrip on This command is used to specify how and when to carry out a linear static analysis. The linear static analysis can either be carried out at time 0 (when=0) or at termination time (when=1). If when=0 the explicit dynamic solver will proceed (until termination time) from the state predicted by the linear static solver. Note that if the termination time (see TIME) is set to 0 only a linear static analysis will be carried out. If when=1 the linear static solver is invoked once the explicit dynamic solver has reached termination time. IMPETUS Afea Solver v.3.0 20 Solu on control and techniques *GPU *GPU sms, elem, blast Parameter defini on Variable Description sms Flag for selective mass scaling and time integration options: 0 → CPU 1 → GPU Flag for element processing options: 0 → CPU 1 → GPU Flag for particle blast calculations options: 0 → CPU 1 → GPU elem blast Descrip on Activate GPU functionality. Requires a CUDA enabled graphics card with compute capability 1.3 or higher. IMPETUS Afea Solver v.3.0 21 Solu on control and techniques *SMS *SMS entype, enid, sf Parameter defini on Variable Description entype Entity type options: P, PS Entity identification number Mass scaling factor enid sf Descrip on Selective mass scaling functionality, as decribed by Olovsson et al. (2005). The critical time step of an element is: ∆tc = √ 1 + sf · ∆tc0 where ∆tc0 is the critical time step without mass scaling. IMPETUS Afea Solver v.3.0 22 Solu on control and techniques *SMS CLUSTER *SMS CLUSTER entype, enid, sf , dmax Parameter defini on Variable Description entype Entity type options: P, PS Entity identification number Mass scaling factor Maximum node distance enid sf dmax Descrip on Selective mass scaling functionality, especially designed for the treatment of small clusters of nodes. The method is similar to SMS. A node belongs to a cluster if it is not further away than dmax from at least one other member of the cluster. IMPETUS Afea Solver v.3.0 23 Solu on control and techniques *TIME *TIME tterm , sf∆t , ∆tmin , ∆tmax , msmax Parameter defini on Variable Description tterm sf∆t Termination time Time step scale factor. It should range between 0 and 1 default: 0.9 Time step size, below which mass scaling will be activated default: 0 Maximum allowed time step size default: 1.0e10 Maximum allowed mass scaling factor on element level default: 1.0e10 ∆tmin ∆tmax msmax Descrip on This command is used to define the duration of the simulated event and to specify parameters controlling the time step size. Note that artificial mass is added if needed in order to prevent the critical time step from dropping below ∆tmin . msmax limits maximum allowed mass scaling factor. IMPETUS Afea Solver v.3.0 24 Output Output *OUTPUT *OUTPUT *OUTPUT *OUTPUT *OUTPUT ELEMENT FORMING NODE SENSOR IMPETUS Afea Solver v.3.0 25 Output *OUTPUT *OUTPUT ∆timp , ∆tascii , ∆tdb nfilter, efilter, entyperes , enidres Parameter defini on Variable Description ∆timp Output interval for complete model (.imp-files) default: ∆timp = tterm /100 Output interval for ASCII data (see list of .out-files in General section) default: ∆tascii = tterm /1000 Output interval for model database and state files. No database or state files will be output if ∆tdb is larger than tterm (see TIME) default: a database file is generated at tterm Filter for node data that will be written to impetus.imp options: 0 → output all node data 1 → output displacements only Filter for element data that will be written to impetus.imp options: 0 → output all element data 1 → output effective stress, plastic strain and damage 2 → output no element data Entity type for state file output. The state file is an ASCII file in command format containing elements, nodes (coordinates and velocities) and contact information. Stresses, strains and state variables are output to a separate binary file. options: P, PS, ALL default: no state file Entity ID for state file output ∆tascii ∆tdb nfilter efilter entyperes enidres Descrip on This command contains output parameters, such as output frequency and filter. The filter is used to reduce the size of the .imp-files. If defining entyperes and enidres , elements, node coordinates and velocities and the current contact state will be written to the ASCII file impetus state1.k. All state variables, stresses and strains are written to a binary file impetus state1.bin. impetus state1.k and impetus state1.bin can be read by IMPETUS Afea Solver. Note that impetus state1.bin is included in a model using the command INCLUDE BINARY. IMPETUS Afea Solver v.3.0 26 Output *OUTPUT ELEMENT *OUTPUT ELEMENT entype, enid Parameter defini on Variable Description entype Entity type options: E, ES Entity identification number enid Descrip on Outputs element results to the ASCII file element.out. IMPETUS Afea Solver v.3.0 27 Output *OUTPUT FORMING *OUTPUT FORMING form Parameter defini on Variable Description form Flag to activate output of sheet thickness options: 0 → do not output sheet thickness 1 → output sheet thickness Descrip on Activates calculation and output of sheet thickness to the .imp-database. IMPETUS Afea Solver v.3.0 28 Output *OUTPUT NODE *OUTPUT NODE entype, enid Parameter defini on Variable Description entype Entity type options: N,NS Entity identification number enid Descrip on Outputs nodal results to the ASCII file node.out IMPETUS Afea Solver v.3.0 29 Output *OUTPUT SENSOR *OUTPUT SENSOR coid, pid, x0 , y0 , z0 , R, csysid Parameter defini on Variable Description coid pid Sensor ID ID of part where the sensor is located options: Part ID or DP for discrete particles Initial x-coordinate of sensor Initial y-coordinate of sensor Initial z-coordinate of sensor Sensor radius (for pid=DP only) Optional local coordinate system ID x0 y0 z0 R csysid Descrip on A sensor can either sample the local state at a material point inside a specified part, or sample the discrete particle state at a specified fixed point in space (see PBLAST[/ref] or [ref]PSOIL). If referring to a part ID, the command will sample the local state at a material point initially located at coordinate (x0 , y0 , z0 ). The solver uses the nearest integration point and node (in the specified part) and outputs the sampled data to the ASCII file sensor.out. If specifying pid=DP (discrete particles) the sensor is fixed in space and will sample the average particle density, velocity and pressure inside a sphere with radius R. The data is then output to the ASCII file pblast sensor.out. Stresses, coordinates, displacements and velocities are output in the local coordinate system (if defined). It is to be noted that displacements are computed relatively the origin of the local system. IMPETUS Afea Solver v.3.0 30 Mesh Commands Mesh Commands *ACTIVATE ELEMENTS *COMPONENT BOLT *COMPONENT BOX *COMPONENT CYLINDER *COMPONENT PIPE *COMPONENT REBAR *COMPONENT SPHERE *MERGE DUPLICATED NODES *REFINE *SMOOTH MESH *TRANSFORM MESH CARTESIAN *TRANSFORM MESH CYLINDRICAL *TRIM *WELD IMPETUS Afea Solver v.3.0 31 Mesh Commands *ACTIVATE ELEMENTS *ACTIVATE ELEMENTS coid, entype, enid, tbirth , tdeath , ξ Parameter defini on Variable Description coid entype Command ID Entity type options: P, PS Entity ID Time or FUNCTION defining element activation Time or FUNCTION defining element deactivation Optional strength of not yet activated elements default: 0 enid tbirth tdeath ξ Descrip on This command lets the user activate or deactivate elements at a pre-defined time or on a certain signal. If a FUNCTION is used an element is activated or deactivated on function values > 0. The optional constant 0 ≤ ξ ≤ 1 is used to scale the internal forces of unactivated elements. ξ is typically used in situations where nodes of unactivated elements are part of a MERGE interface and where the nodes need to be active from time 0 to avoid the formation of gaps. A typical application is weld seams where the weld elements need to follow the deformation of the base material. Else they will not be activated at the correct location. IMPETUS Afea Solver v.3.0 32 Mesh Commands *COMPONENT BOLT *COMPONENT BOLT coid, pid1 , pid2 , pid3 , pid4 , csysid D, L, h, t Parameter defini on Variable Description coid pid1 Component ID Bolt part ID default: no bolt Nut part ID default: no nut Washer 1 part ID default: no washer Washer 2 part ID default: no washer Local coordinate system ID default: global coordinates are used Bolt diameter Bolt length Axial distance between washers Washer thickness pid2 pid3 pid4 csysid D L h t Descrip on This command is used to define and position a bolt. IMPETUS Afea Solver v.3.0 33 Mesh Commands *COMPONENT BOX *COMPONENT BOX coid, pid, Nx , Ny , Nz , csysid x 1 , y1 , z 1 , x 2 , y2 , z 2 Parameter defini on Variable Description coid pid Nx Ny Nz csysid Component ID Part ID Number of elements in local x-direction Number of elements in local y-direction Number of elements in local z-direction Local coordinate system ID default: global coordinates are used Box corner coordinate 1 Box corner coordinate 2 x1 , y1 , z1 x2 , y2 , z2 Descrip on This command is used to define a box with part ID pid. IMPETUS Afea Solver v.3.0 34 Mesh Commands *COMPONENT CYLINDER *COMPONENT CYLINDER coid, pid, N1 , N2 , csysid x1 , y1 , z1 , x2 , y2 , z2 , R1 , R2 Parameter defini on Variable Description coid pid N1 N2 csysid Component ID Part ID Number of elements in axial direction Mesh density parameter Local coordinate system ID default: global coordinates are used Face center coordinate 1 Face center coordinate 2 Radius at face 1 Radius at face 2 default: R2 = R1 x1 , y1 , z1 x2 , y2 , z2 R1 R2 Descrip on This command is used to define a solid cylinder with part ID pid. IMPETUS Afea Solver v.3.0 35 Mesh Commands *COMPONENT PIPE *COMPONENT PIPE coid, pid, N1 , N2 , N3 , csysid, αc x1 , y1 , z1 , x2 , y2 , z2 , R1 , R2 R3 , R4 Parameter defini on Variable Description coid pid N1 N2 N3 csysid Component ID Part ID Number of elements in axial direction Number of elements in circumferetial direction Number of elements in thickness direction Local coordinate system ID default: global coordinates are used Angle in circumferential direction default: 360◦ (full pipe) Face center coordinate 1 Face center coordinate 2 First radius at x1 Second radius at x1 First radius at x2 default: R3 =R1 Second radius at x2 default: R4 =R2 αc x1 , y1 , z1 x2 , y2 , z2 R1 R2 R3 R4 Descrip on This command is used to define a pipe with part ID pid. Note that the smaller of R1 , R2 (and R3 , R4 ) is automatically taken as the inner radius. IMPETUS Afea Solver v.3.0 36 Mesh Commands *COMPONENT SPHERE *COMPONENT SPHERE coid, pid, N, Nc , csysid, αc x0 , y0 , z0 , R1 , R2 Parameter defini on Variable Description coid pid N Nc csysid Component ID Part ID Mesh density parameter (see figure below) Number of elements in circumferential direction (only used if αc 6= 360◦ ) Local coordinate system ID default: global coordinates are used Angle in circumferential direction default: 360◦ (full sphere) Sphere center coordinate Sphere radius 1 Sphere radius 2 αc x0 , y0 , z0 R1 R2 Descrip on This command is used to define a sphere with part ID pid. A hollow sphere is generated if both R1 and R2 are non-zero. IMPETUS Afea Solver v.3.0 37 Mesh Commands *MERGE DUPLICATED NODES *MERGE DUPLICATED NODES entypes , enids , entypem , enidm , tol Parameter defini on Variable Description entypes Slave entity type options: P, PS Slave entity identification number Master entity type options: P, PS Master entity identification number Tolerance for merging nodes default: 0 enids entypem enidm tol Descrip on This command is used to merge duplicated nodes. IMPETUS Afea Solver v.3.0 38 Mesh Commands *REFINE *REFINE entype, enid, level, gid, no thick, dmin , αmax Parameter defini on Variable Description entype Entity type options: P, PS Entity identification number Level of refinement ID of a GEOMETRY that defines a sub-space for refinement default: all elements in the selected part/part set will be refined Disables refinement in through thickness direction options: 0 → refinement in plate thickness direction is allowed 1 → refinement in plate thickness direction is turned off Minimum element dimension for refinement default: all elements are refined External element face smoothing angle default: no surface smoothing enid level gid no thick dmin αmax Descrip on This command is used to refine the grid in a selected region of a part or part set. Pentahedra and tetrahedra elements can currently only handle refinement level = 2. The surface of the refined region is smoothed if the angle between two adjacent element faces is smaller than or equal to αmax . IMPETUS Afea Solver v.3.0 39 Mesh Commands *SMOOTH MESH *SMOOTH MESH entype, enid, αmax , internal Parameter defini on Variable Description entype Entity type options: N, NS, P, PS, G, ALL Entity identification number External element face smoothing angle Flag to activate smoothing of internal material interfaces and to propagate smoothing to internal nodes options: 0 → only smoothing of external material surface 1 → internal smnoothing activated enid αmax internal Descrip on This command is used to smooth the surface of quadratic and cubic element surfaces. The surface is smoothed if the angle between two adjacent element faces is smaller than or equal to αmax . By default, only external element faces are smoothed. The internal flag turns on smoothing of internal material interfaces and also propagates the surface smoothing to the interior of the mesh. IMPETUS Afea Solver v.3.0 40 Mesh Commands *TRANSFORM MESH CARTESIAN *TRANSFORM MESH CARTESIAN coid, entype, enid, csysid, fid1 , fid2 , fid3 Parameter defini on Variable Description coid entype Command ID Entity type options: G, GS, P, PS Entity ID Local coordinate system ID default: global coordinates are used FUNCTION defining the displacement in local x-direction FUNCTION defining the displacement in local y-direction FUNCTION defining the displacement in local z-direction enid csysid fid1 fid2 fid3 Descrip on This command is used to transform a mesh. The transformation is expressed as diplacements in global or local cartesian coordinates. A local system is used if csysid is defined. IMPETUS Afea Solver v.3.0 41 Mesh Commands *TRANSFORM MESH CYLINDRICAL *TRANSFORM MESH CYLINDRICAL coid, entype, enid, csysid, fid1 , fid2 , fid3 , fid4 Parameter defini on Variable Description coid entype Command ID Entity type options: G, GS, P, PS Entity ID ID of cylindrical coordinate system FUNCTION defining radial displacement of inner surface FUNCTION defining radial displacement of outer surface FUNCTION defining axial displacement FUNCTION defining tangential displacement enid csysid fid1 fid2 fid3 fid4 Descrip on This command is used to transform a mesh. The transformation is expressed as diplacements in cylindrical coordinates (R, z, θ). R is the radius, z is the axial coordinate and θ is a circumferential angle ranging from 0◦ to 360◦ . If fid1 6= fid2 inner and outer surfaces use different radial transformations (see example below). In such situations only nodes on the surface of the body are transformed. Interior nodes are not treated. However, all nodes are transformed in the radial direction if fid1 = fid2 . Figure 1: Interior and exterior surfaces IMPETUS Afea Solver v.3.0 42 Mesh Commands *TRIM *TRIM entype, enid, nidseed , ttrim , x ˆ, yˆ, zˆ x 1 , y1 , z 1 . x n , yn , z n Parameter defini on Variable Description entype Entity type options: P, PS Entity ID Seed node id, marking material to keep after trimming Trim time X-component of trimline projection direction Y-component of trimline projection direction Z-component of trimline projection direction X-coordinate of trim line point 1 Y-coordinate of trim line point 1 Z-coordinate of trim line point 1 X-coordinate of trim line point n Y-coordinate of trim line point n Z-coordinate of trim line point n enid nidseed ttrim x ˆ yˆ zˆ x1 y1 z1 xn yn zn Descrip on Trimming function for metal stamping applications. The trim path is a discretized line, defined by a list of coordinates. IMPETUS Afea Solver v.3.0 43 Mesh Commands *WELD *WELD nsid, stype, pid, nseg, a, rof f Parameter defini on Variable Description nsid stype ID of node set defining weld path Weld cross section discretization options: 1 → 1 triangle 2 → 3 quads 3 → 1 quad Part ID of generated weld mesh Number of elements along weld path default: Same discretization as the weld path Weld thickness (a-value) Weld root offset pid nseg a rof f Descrip on This command is used to generate the mesh of a weld seam. The solver terminates immediately after outputting the generated grid to the file weld.k. The weld seam is to be connected to the welded parts with the MERGE command. The mechanical properties in the heat affected zone (HAZ) can be accounted for by importing results from WeldSim (TM) through the command INITIAL STATE WELDSIM[/ref], or by manually defing properties through [ref]INITIAL STATE HAZ. Note that a weld root offset (rof f > 0) requires a 1-quad section (stype = 3). The 1-quad section is not allowed if rof f = 0. IMPETUS Afea Solver v.3.0 44 Nodes and connec vity Nodes and connec vity *CHANGE P-ORDER *ELEMENT CHEX *ELEMENT CPRISM *ELEMENT CTET *ELEMENT QHEX *ELEMENT QPRISM *ELEMENT QTET *ELEMENT REBAR *ELEMENT SHELL *ELEMENT SOLID *NODE *PART IMPETUS Afea Solver v.3.0 45 Nodes and connec vity *CHANGE P-ORDER *CHANGE P-ORDER entype, enid, order, gid Parameter defini on Variable Description entype Entity type options: P, PS, ALL Entity identification number New element polynomial order options: 1, 2, 3 ID of a GEOMETRY that defines a sub-space for change of polynomial order default: No geometry. This means that all elements in the selected part/part set will change polynomial order enid order gid Descrip on Change element polynomial order in a selected region of a part or part set. IMPETUS Afea Solver v.3.0 46 Nodes and connec vity *ELEMENT CHEX *ELEMENT CHEX eid, pid nid01 , ... , nid10 nid11 , ... , nid20 nid21 , ... , nid30 nid31 , ... , nid40 nid41 , ... , nid50 nid51 , ... , nid60 nid61 , ... , nid64 Parameter defini on Variable Description eid pid nid01 , nid11 , nid21 , nid31 , nid41 , nid51 , nid61 , Unique element identification number Part identification number Element nodes 01 - 10 Element nodes 11 - 20 Element nodes 21 - 30 Element nodes 31 - 40 Element nodes 41 - 50 Element nodes 51 - 60 Element nodes 61 - 64 ... ... ... ... ... ... ... , , , , , , , nid10 nid20 nid30 nid40 nid50 nid60 nid64 Descrip on Cubic hexahedron element definition. Figure 2: Cubic hexahedron 1 - Corner and edge nodes IMPETUS Afea Solver v.3.0 47 Nodes and connec vity Figure 3: Cubic hexahedron 2 - Face nodes Figure 4: Cubic hexahedron 3 - Internal nodes IMPETUS Afea Solver v.3.0 48 Nodes and connec vity *ELEMENT CPRISM *ELEMENT CPRISM eid, pid nid01 , ... , nid10 nid11 , ... , nid20 nid21 , ... , nid30 nid31 , ... , nid40 Parameter defini on Variable Description eid pid nid01 , nid11 , nid21 , nid31 , Unique element identification number Part identification number Element nodes 01 - 10 Element nodes 11 - 20 Element nodes 21 - 30 Element nodes 31 - 40 ... ... ... ... , , , , nid10 nid20 nid30 nid40 Descrip on Cubic pentahedron (wedge, cake) element definition. Figure 5: Cubic pentahedron 1 - Corner and edge nodes IMPETUS Afea Solver v.3.0 49 Nodes and connec vity Figure 6: Cubic pentahedron 2 - Face nodes Figure 7: Cubic pentahedron 3 - Internal nodes IMPETUS Afea Solver v.3.0 50 Nodes and connec vity *ELEMENT CTET *ELEMENT CTET eid, pid nid01 , ... , nid10 nid11 , ... , nid20 Parameter defini on Variable Description eid pid nid01 , ... , nid10 nid11 , ... , nid20 Unique element identification number Part identification number Element nodes 01 - 10 Element nodes 11 - 20 Descrip on Cubic tetrahedron element definition. Figure 8: Cubic tetrahedron 1 - Corner and edge nodes IMPETUS Afea Solver v.3.0 51 Nodes and connec vity Figure 9: Cubic tetrahedron 2 - Face nodes IMPETUS Afea Solver v.3.0 52 Nodes and connec vity *ELEMENT QHEX *ELEMENT QHEX eid, pid nid01 , ... , nid10 nid11 , ... , nid20 nid21 , ... , nid27 Parameter defini on Variable Description eid pid nid01 , ... , nid10 nid11 , ... , nid20 nid21 , ... , nid27 Unique element identification number Part identification number Element nodes 01 - 10 Element nodes 11 - 20 Element nodes 21 - 27 Descrip on Quadratic hexahedron element definition. Figure 10: Quadratic hexahedron 1 - Corner and edge nodes IMPETUS Afea Solver v.3.0 53 Nodes and connec vity Figure 11: Quadratic hexahedron 2 - Face nodes IMPETUS Afea Solver v.3.0 54 Nodes and connec vity *ELEMENT QPRISM *ELEMENT QPRISM eid, pid, nid01 , ... , nid08 nid09 , ... , nid18 Parameter defini on Variable Description eid pid nid01 , ... , nid08 nid09 , ... , nid18 Unique element identification number Part identification number Element nodes 01 - 08 Element nodes 09 - 18 Descrip on Quadratic pentahedron (wedge, cake) element definition. Figure 12: Quadratic pentahedron 1 - Corner and edge nodes IMPETUS Afea Solver v.3.0 55 Nodes and connec vity Figure 13: Quadratic pentahedron 2 - Face nodes IMPETUS Afea Solver v.3.0 56 Nodes and connec vity *ELEMENT QTET *ELEMENT QTET eid, pid nid1 , ... , nid10 Parameter defini on Variable Description eid pid nid1 , ... , nid10 Unique element identification number Part identification number Element nodes 1 - 10 Descrip on Quadratic tetrahedron element definition. Figure 14: Quadratic tetrahedron - a solid element with 10 nodes IMPETUS Afea Solver v.3.0 57 Nodes and connec vity *ELEMENT SHELL *ELEMENT SHELL eid, pid, nid1 , nid2 , nid3 , nid4 Parameter defini on Variable Description eid pid nid1 nid2 nid3 nid4 Unique element identification number Part identification number Element node 1 Element node 2 Element node 3 Element node 4 Descrip on Linear triangular or quadrilateral shell element definition. Currently only for use with MAT RIGID. IMPETUS Afea Solver v.3.0 58 Nodes and connec vity *ELEMENT SOLID *ELEMENT SOLID eid, pid, nid1 , nid2 , nid3 , nid4 , nid5 , nid6 , nid7 , nid8 Parameter defini on Variable Description eid pid nid1 nid2 nid3 nid4 nid5 nid6 nid7 nid8 Unique element identification number Part identification number Element node 1 Element node 2 Element node 3 Element node 4 Element node 5 Element node 6 Element node 7 Element node 8 Descrip on Defines a solid element. linear tetrahedron = 4 nodes: eid, pid, nid1 , nid2 , nid3 , nid4 , nid4 , nid4 , nid4 , nid4 Figure 15: Linear tetrahedron - Solid element with four nodes linear hexahedron = 8 nodes: eid, pid, nid1 , nid2 , nid3 , nid4 , nid5 , nid6 , nid7 , nid8 linear pentahedron = 6 nodes: eid, pid, nid1 , nid2 , nid3 , nid4 , nid5 , nid5 , nid6 , nid6 IMPETUS Afea Solver v.3.0 59 Nodes and connec vity Figure 16: Linear hexahedron - Solid element with eight nodes Figure 17: Linear pentahedron - Solid element with six nodes IMPETUS Afea Solver v.3.0 60 Nodes and connec vity *NODE *NODE nid, x, y, z, bc Parameter defini on Variable Description nid x, y, z bc Unique node identification number Node coordinate Translational constraint options: 0, X, Y, Z, XY, YZ, ZX, XYZ Descrip on Defines a node. IMPETUS Afea Solver v.3.0 61 Nodes and connec vity *PART *PART erode pid, mid, eosid, h, αmax , ∆terode , erode geo , v Parameter defini on Variable Description pid mid eosid Unique part identification number or range of parts Material identification number Equation-of-state identification number default: equation-of-state is not used Shell thickness (only used for mass calculation, not in contact) or rebar diameter default: 1 External element face smoothing angle default: no surface smoothing, i.e. ang smooth = 0◦ Time step size below which elements are eroded default: 0 Effective deviatoric geometric strain above which elements are eroded default: 1.0e20 Volumetric strain above which elements are eroded default: 1.0e20 h αmax ∆terode erode geo erode v Descrip on The command is used to assign properties to a part or to a range of parts. Surface smoothing is applied if the angle between the normal vectors of two adjacent higher order external faces is smaller than αmax . Part commands can be assigned a title. The title shows up in part.out and in the part list in IMPETUS Afea Visualizer. An element is eroded if its critical time step drops below ∆terode , if the effective deviatoric geometrical strain geo erode . The effective deviatoric reaches erode geo in at least one integration point, or if the volumetric strain exceeds v geometric strain is defined as: √ 2 dev : dev geo = 3 where dev is the deviatoric strain tensor. Note that elements can also be eroded at material failure if setting the erosion flag to 1 in the damage property command. IMPETUS Afea Solver v.3.0 62 Material proper es Material proper es *EOS GRUNEISEN *EOS POLYNOMIAL *EOS TAIT *MAT CERAMIC *MAT CONCRETE *MAT CREEP *MAT ELASTIC *MAT FLUID *MAT FOAM *MAT FORMING *MAT FORMING R *MAT GRANULAR CAP *MAT HJC CONCRETE *MAT JC *MAT JC FIELD *MAT JH CERAMIC *MAT LIBRARY *MAT METAL *MAT MOONEY RIVLIN *MAT MULTILAYER ORTHOTROPIC *MAT ORTHOTROPIC *MAT PWL *MAT REBAR *MAT RIGID *MAT USER JS *MAT USER X *MAT VISCO PLASTIC IMPETUS Afea Solver v.3.0 63 Material proper es *PROP *PROP *PROP *PROP *PROP *PROP *PROP *PROP DAMAGE BRITTLE DAMAGE CL DAMAGE CL ANISOTROPIC DAMAGE IMP DAMAGE IMP ISO DAMAGE JC DAMAGE STRAIN THERMAL IMPETUS Afea Solver v.3.0 64 Material proper es *EOS GRUNEISEN *EOS GRUNEISEN eosid, S, Γ Parameter defini on Variable Description eosid S Γ Unique EOS identification number Linear Hugoniot slope coefficient Gruneisen gamma Descrip on This is the Mie-Gruneisen equation-of-state. Note that the linear bulk modulus, K, is determined from the elastic properties in the material command. ) ( Kη Γη p= + Γρ0 e · 1− (1 − Sη)2 2 where ρ is the current density, ρ0 is the initial density and e is the specific internal energy. η is a measure of the volumetric compression. η =1− IMPETUS Afea Solver v.3.0 ρ0 ρ 65 Material proper es *EOS POLYNOMIAL *EOS POLYNOMIAL eosid, A, B, C Parameter defini on Variable Description eosid A B C Unique EOS identification number Polynomial coefficient Polynomial coefficient Polynomial coefficient Descrip on This is a polynomial equation-of-state that currently only works with SPH particles. Note that the linear bulk modulus, K, is determined from the elastic properties in the material command. p = Kµ + Aµ2 + B + Cµ e 1+µ where e is the specific internal energy per unit volume and µ is a measure of the volumetric compression. µ= IMPETUS Afea Solver v.3.0 ρ −1 ρ0 66 Material proper es *EOS TAIT *EOS TAIT eosid, γ Parameter defini on Variable Description eosid γ Unique EOS identification number Exponent in pressure-density relationship Descrip on This equation-of-state currently only works with SPH particles. Note that the linear bulk modulus, K, is determined from the elastic properties in the material command. ) (( )γ ρ −1 p=K ρ0 IMPETUS Afea Solver v.3.0 67 Material proper es *MAT CERAMIC *MAT CERAMIC mid, ρ, G A0 , B0 , Af , Bf , f , Kc , ts , αs K1 , K2 , K3 , β Parameter defini on Variable Description mid ρ G A0 B0 Af Bf f Kc ts αs K1 K2 K3 β Unique material identification number Density Shear modulus Yield surface parameter Yield surface parameter Failure surface parameter Failure surface parameter Volumetric crushing strain Fracture toughness Time to develop spall fracture at threshold stress Exponent controlling time to develop spall fracture Linear bulk stiffness term Quadratic bulk stiffness term Cubic bulk stiffness term Parameter controlling the plastic flow direction at crushing. β must be larger than 0 and can not exceed 1. default: 1 → associated plastic flow Descrip on This is a ceramic model with different failure mechanisms in compression and tension. The material is assumed to have a pressure dependent shear resistance. At positive pressures, plastic flow is a combination of shearing and dilatation. Inelastic dilatation is interpreted as crushing that gradually reduces the shear resistance of the material. A brittle fracture criterion combined with node splitting is used on the tensile side. For positive pressures the yield function Φ is defined as: Φ = σef f − σ0 · (1 − Dc ) − σf · Dc where: σ0 = A0 + B0 · p σf = Af + Bf · p IMPETUS Afea Solver v.3.0 68 Material proper es Further, σef f is the effective von Mises stress, p is the pressure and Dc is a crushing damage parameter ranging from 0 to 1. The inelastic flow direction is defined as: ∂Φ ˙pvol = β λ˙ ∂p ∂Φ ˙pdev = λ˙ ∂σef f Here pvol is a volumetric crushing strain and pdev is a deviatoric inelastic shear strain. 0 < β ≤ 1 is controlling the amount of volumetric dilatation during plastic flow. Note that β must be larger than 0 as the evolution of the crushing damage parameter Dc is driven by pvol . Dc = min(1, pvol ) f A brittle failure criterion is used for p < 0. Cracks initiate once a damage parameter, Ds , has evolved from 0 to 1. 1 σ1 αs ·( ) σ1 ≥ σs ˙ Ds = t σ s 0s σ <σ 1 s where σ1 is the maximum principal stress and σs is the spall stress. σs = [A0 · (1 − Dc ) + Af · Dc ] · (1 − D0 ) D0 is an optional initial defect (damage) value that can be defined through INITIAL DAMAGE RANDOM[/ref] or [ref]INITIAL DAMAGE SURFACE RANDOM. Accounting for initial defects is essential for a physically realistic behavior of many brittle materials. It is generally more important when dealing with relatively small material volumes. Crack propagation is controlled by a stress intensity criterion. The stress intensity KI is estimated for the integration points surrounding the crack tip. The crack will propagate if KI > Kc (Modus I crack). The pressure-volume relationship is cubic in compression: p = K1 (µ + pvol ) + K2 µ2 + K3 µ3 µ > 0 and linear in tension: p = K1 (µ + pvol ) µ < 0 where: µ = ρ/ρ0 − 1 IMPETUS Afea Solver v.3.0 69 Material proper es Figure 18: Yield stress as a function of pressure and damage IMPETUS Afea Solver v.3.0 70 Material proper es *MAT CREEP *MAT CREEP mid, ρ, E, ν, did, tid A, B, n, c0 , c1 , c2 , c3 Parameter defini on Variable Description mid ρ E Unique material identification number Density Young’s modulus, constant of function of temperature options: constant, fcn Poisson’s ratio, constant of function of temperature options: constant, fcn Damage property command ID Thermal property command ID Initial yield strength, constant or function of temperature options: constant, fcn Hardening parameter, constant of function of temperature options: constant, fcn Hardening exponent, constant of function of temperature options: constant, fcn Creep parameter, constant of function of temperature options: constant, fcn Creep parameter, constant of function of temperature options: constant, fcn Creep parameter, constant of function of temperature options: constant, fcn Creep parameter, constant of function of temperature options: constant, fcn ν did tid A B n c0 c1 c2 c3 Descrip on This model combines a plastic yield surface (J2) with a visco-plastic creep law. All inelastic flow follows a simple radial return law. The total strain is assumed additive: = e + p + c where e stands for elastic, p plastic and c for creep. The plastic yield stress is: [ ]n(T ) σy = A(T ) + B(T ) pef f The creep strain rate is: IMPETUS Afea Solver v.3.0 71 Material proper es [ ˙cef f σef f = c1 (T ) + c2 (T )cef f + c3 (T )(cef f )2 ]c0 (T ) The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 72 Material proper es *MAT ELASTIC *MAT ELASTIC mid, ρ, E, ν, did, tid a, b, c, cdec Parameter defini on Variable Description mid ρ E ν did tid a, b c cdec Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID Thermal property command ID Non-linear elasticity parameters Damping coefficient Damping decay coefficient Descrip on A non-linear elastic constitutive model with damping. The stress is defined as: ∫ t c geo 2 σ = −pI + 2G · [1 + ageo + b( ) ] · + (τ ˙ ) · e(τ −t)/cdec dτ dev dev dev cdec 0 G is the shear modulus, dev is the deviatoric strain and geo dev is the effective deviatoric geometric strain. √ 2 geo dev = dev : dev 3 The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 73 Material proper es *MAT FLUID *MAT FLUID mid, ρ, K, µ, pc G Parameter defini on Variable Description mid ρ K µ pc Unique material identification number Density Linear bulk modulus Viscosity Pressure cut-off default: -1.0e15 Artificial shear modulus (Finite elements only) default: no artifical shear stiffness G Descrip on This is a simple fluid model. It can be combined with an equation-of-state for a non-linear pressure-volume relationship. IMPETUS Afea Solver v.3.0 74 Material proper es *MAT FOAM *MAT FOAM mid, ρ, E, ν, did cid, tsc, β Parameter defini on Variable Description mid ρ E ν did cid Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress versus volumetric compression Tensile stress cut-off (a positive value should be given) Damping coefficient for strain rate sensitivity (β > 0.1 is recommended) tsc β Descrip on MAT FOAM is a simple model for crushable foams. This model is limited to isotropic behaviour under impact loading conditions (non-cyclic loading). Figure 19: Stress-strain behaviour The implementation assumes a constant Young’s modulus (E) and elastic behaviour for stress update. Trial stress is thus evaluated as: 1 1 trial n σij = σij + 3K( ∆kk δij ) + 2G(∆ij − ∆kk δij ) 3 3 where K is the bulk modulus and G is the shear modulus. Principal stresses σItrial (I=1,3) are then computed and the following criterion is checked: σ trial trial σI > σcompaction ⇒ σIn+1 = σcompaction Itrial σI IMPETUS Afea Solver v.3.0 75 Material proper es The compaction curve is defined by a CURVE (compaction pressure/volumetric strain). This is done independently in each direction, implying no Poisson effect. Principal stresses are optionally limited in tension by a tension cut-off parameter (elastic perfectly plastic behaviour). A damping coefficient is also possibly defined in order to take into account rate sensitivity. Minimal recommended damping coefficient value is 0.1. This adds an extra damping stress as follows: damping σij = β · ρ · Lelement · clong · i˙j where β is the damping coefficient, ρ is the density, Lelement is the characteristic element length and clong is the longitudinal sound speed. IMPETUS Afea Solver v.3.0 76 Material proper es *MAT FORMING *MAT FORMING mid, ρ, E, ν, did, tid cid, ξ, a0 , a1 1 , 2 , 3 , σ1 , σ2 , σ3 , csysid Parameter defini on Variable Description mid ρ E ν did tid cid Unique material identification number Density Young’s modulus Poisson’s ratio Damage model ID Thermal property command ID ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress versus plastic strain (equivalent measures) Kinematical hardening parameter ranging from 0 to 1 default: 0 (pure iso-tropic hardening) Plastic hardening parameter Parameter controlling the shape of the yield surface Initial principal plastic strains Initial back stress in principal strain directions ID of coordinate system that defines the directions of the initial principal strains and stresses default: use global directions ξ a0 a1 1 , 2 , 3 σ1 , σ2 , σ3 csysid Descrip on A texture-based forming model developed by Impetus Afea. The effective stress is defined as: √ ] 3[ 2 2 +b σ 2 2 +σ 2 +σ 2 ) σef f = b1 σ ˆ11 + b2 σ ˆ22 σ12 ˆ23 ˆ31 3 ˆ33 + 2b0 (ˆ 2 where: σ ˆ = Q [σdev − σ ∗ ] Qt σdev is the deviatoric stress, σ ∗ is the back stress due to kinematical hardening and Q is a tensor that transforms the stress tensor to principal strain directions. b1 , b2 and b3 are parameters that control the difference in flow stress in different principal strain directions. This is motivated by crystallographic texture effects. ( ) |i | bi = 1 + a1 1 − atan(ˆ geo ) ˆgeo IMPETUS Afea Solver v.3.0 77 Material proper es where ˆgeo is an effective geometric strain measure: √ ˆgeo = 25 2 ( + 22 + 23 ) 54 1 The definition of ˆgeo ensures that the force displacement curve in uni-axial tension does not depend on the parameter a1 . b0 is a parameter that ensures a larger flow stress in the principal strain directions than in other loading directions. This is also motivated by crystallographic texture effects. b0 = 1 + a0 ˆgeo The degree of kinematical hardening is controlled by ξ, a parameter ranging from 0 to 1. ξ = 0 results in pure iso-tropic hardening (growing yield surface) and ξ = 1 in pure kinematical hardening (translating yield surface). The evolution of the back stress is: σ˙ ∗ = ξH ˙p and the radius of the yield surface grows according to: σ˙ y = (1 − ξ)H ˙p H is the tangential hardening and it is defined as: H= dσy (σef f = σy ) dpef f The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref f is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 78 Material proper es *MAT FORMING R *MAT FORMING R mid, ρ, E, ν, did, tid cid, ξ, R00 , R45 , R90 Parameter defini on Variable Description mid ρ E ν did tid cid Unique material identification number Density Young’s modulus Poisson’s ratio Damage model ID Thermal property command ID ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress versus plastic strain (equivalent measures) Kinematical hardening parameter ranging from 0 to 1 default: 0 (pure iso-tropic hardening) Lankford coefficient Lankford coefficient Lankford coefficient ξ R00 R45 R90 Descrip on This is a plasticity model where kinematical hardening and Lankford parameters can be defined as constants or as functions of the effective plastic strain. A J2 (von Mises) yield criterion is combined with a non-assiciated flow rule. The non-associated flow rule is defined to satisfy the given Lankford parameters. Initial material orientation is defined using either INITIAL MATERIAL DIRECTION[/ref], [ref]INITIAL MATERIAL DIRECTI or [ref]INITIAL MATERIAL DIRECTION WRAP. IMPETUS Afea Solver v.3.0 79 Material proper es *MAT GRANULAR CAP *MAT GRANULAR CAP mid, ρ, E, ν max , B , B cid1 , cid2 , ξ, η, σdev 0 1 Parameter defini on Variable Description mid ρ E ν cid1 cid2 Unique material identification number Density Young’s modulus Poisson’s ratio ID of a CURVE[/ref] or [ref]FUNCTION defining pressure versus volumetric compaction ID of a CURVE[/ref] or [ref]FUNCTION defining deviatoric yield stress due to grain adhesion default: no adhesion Parameter controlling the shape of the yield surface Parameter controlling the shape of the yield surface Upper cap to deviatoric yield strength default: no upper cap Failure parameter default: no failure Failure parameter default: 0 ξ η max σdev B0 B1 Descrip on This is a material model for granular media, where inelastic deviatoric flow and volumetric flow are coupled. The shape of the yield surface is shown in the figure below. Note that the yield surface is split into two regions (I) and (II). Volumetric flow (compaction) is assumed to only occur in region II (associated flow). Plastic flow in region I is purely deviatoric (J2). In region II the surface is elliptic: v( ) u u σ ef f 2 ( p − ξp )2 c t dev + −1 Φ= ξpc pc − ξpc cid1 describes the compaction pressure as function of the effective volumetric strain: f pc = pˆc (ef vol ). cid2 describes the grain adhesion due to compaction (see yield surface in figure): f σa = σ ˆa (ef vol ). IMPETUS Afea Solver v.3.0 80 Material proper es Damage D is assumed to grow at inelastic deviatoric deformations in region I: ˙ef f D˙ = dev B0 ( ) p B1 1− pc Damage falls back to zero whenever the material undergoes further compaction (region II). As D reaches 1 the adhesive components of the yield stress are set to zero and pressure is not allowed to drop below 0. D is set to 1 (instant failure) if meeting the pressure cut-off criterion, i.e. if p = −σa . Figure 20: Yield surface and flow law IMPETUS Afea Solver v.3.0 81 Material proper es *MAT HJC CONCRETE *MAT HJC CONCRETE mid, ρ, G A, B, n, C, fc , T , ˙0 , efmin sfmax , pc , µc , pl , µl , D1 , D2 , K1 K2 , K3 , erode Parameter defini on Variable Description mid ρ G A B n C fc T ˙0 efmin sfmax pc µc pl µl D1 D2 K1 K2 K3 erode Unique material identification number Density Shear modulus Cohesive strength parameter Pressure hardening parameter Pressure hardening parameter Strain rate parameter Compressive strength Tensile strength Reference strain rate Minimum fracture strain Maximum strength Crush pressure Crush volumetric strain Lock pressure Lock volumetric strain Failure strain parameter Failure strain parameter Linear bulk stiffness term Quadratic bulk stiffness term Cubic bulk stiffness term Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded Descrip on This is the Holmquist-Johnson-Cook concrete model. In the postive pressure regime the deviatoric flow stress σy is defined as: [ ( ( )N ) ( ( ))] p ˙ σy = f c · min sfmax , A(1 − D) + B · 1 + Cln fc ˙0 and in the negative pressure (tensile) regime as: IMPETUS Afea Solver v.3.0 82 Material proper es ( ( )) ˙ σy = f c · A(1 + p/T ) · (1 − D) · 1 + Cln ˙0 where p is the current pressure and 0 ≤ D ≤ 1 is the damage. Damage grows during crushing and deviatoric plastic flow according to: ˙p + µ˙ p D˙ = f ˙p and µ˙ p are the deviatoric and volumetric plastic strain rates, respectively. The failure strain f is defined as: ( ( ) ) p + T D2 f = max efmin , D1 fc The pressure-volumetric strain relationship is divided into three regions. Region I is linear elastic and is valid from p = −T to p = pc . The bulk modulus in region I is K0 = pc /µc . Region II is transition region where pressure grows from pc to pl . The bulk modulus in region II is interpolated linearly from K0 at p = pc to K1 at p = pl . The material is fully compacted at p = pl . Region III describes the fully compacted material. There are no more voids and the pressure is defined as: p = K1 µ ˆ + K2 µ ˆ2 + K3 µ ˆ3 where: µ ˆ= IMPETUS Afea Solver v.3.0 µ − µl 1 + µl 83 Material proper es *MAT JC *MAT JC mid, ρ, E, ν, did, tid A, B, n, C, m, T0 , Tm , 0 Cp , k Parameter defini on Variable Description mid ρ E ν did tid A B n C m T0 Tm 0 Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID Thermal property command ID Initial yield strength Hardening parameter Hardening parameter Strain rate hardening parameter Thermal softening parameter Ambient temperature Melting temperature Strain rate parameter default: 1 Specific heat capacity Plastic work to heat conversion factor default: 0.9 Cp k Descrip on Johnson-Cook’s constitutive model. The von Mises flow stress is defined as: ( ( p )) ( ( ) ) ( ) ˙ef f T − T0 m p n σy = A + B(ef f ) · 1 + C · ln · 1− 0 Tm − T0 T is the current temperature. The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 84 Material proper es *MAT JC FIELD *MAT JC FIELD mid, ρ, E, ν, did, tid A, B, n, C, m, T0 , Tm , 0 Cp , k, Wc0 , c1 , c2 , erode Parameter defini on Variable Description mid ρ E ν did tid A B n C m T0 Tm 0 Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID Thermal property command ID Initial yield strength Hardening parameter Hardening parameter Strain rate hardening parameter Thermal softening parameter Ambient temperature Melting temperature Strain rate parameter default: 1 Specific heat capacity Plastic work to heat conversion factor default: 0.9 Cockcroft-Latham damage parameter default: damage not active Extended rate dependency parameter to the Cockcroft-Latham damage criterion default: not active Extended rate dependency parameter to the Cockcroft-Latham damage criterion default: not active Element erosion flag options: 0 → failed elements keep the bulk stiffness 1 → failed elements are eroded 2 → node splitting Cp k Wc0 c1 c2 erode Descrip on Field version of Johnson-Cook’s constitutive model. All parameters (including density) can be functions or parameters. A function can be defined to depend on the initial integration point location (x, y, z). A function is referenced by typing fcn(id), where id is the function ID. The von Mises flow stress is defined as: ( ( p )) ( ( ) ) ( ) ˙ef f T − T0 m p n σy = A + B(ef f ) · 1 + C · ln · 1− 0 Tm − T0 IMPETUS Afea Solver v.3.0 85 Material proper es T is the current temperature. The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref f is the reference temperature (see PROP THERMAL). Failure modeling is currently limited to a Cockcroft-Latham criterion that has been extended to account for rate effects. Failure occurs once the damage parameter, D, has evolved from 0 to 1. ∫ D= 0 IMPETUS Afea Solver v.3.0 pef f max(0, σ1 ) dpef f p c 2 Wc0 · (1 + c1 ˙ef f ) 86 Material proper es *MAT JH CERAMIC *MAT JH CERAMIC mid, ρ, G A, B, C, m, n, ˙0 , T HEL, pH , β, D1 , D2 , K1 , K2 , K3 erode Parameter defini on Variable Description mid ρ G A B C m n ˙0 T HEL pH β Unique material identification number Density Shear modulus Yield surface parameter Failure surface parameter Strain rate parameter Failure surface parameter Yield surface parameter Reference strain rate Strength in hydrostatic tension Uni-axial stress at Hugoniot elastic limit Pressure at Hugoniot elastic limit Fraction of elastic energy loss due to damage that is converted to hydrostatic energy (pressure) Failure strain parameter Failure strain parameter Linear bulk stiffness term Quadratic bulk stiffness term Cubic bulk stiffness term Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded D1 D2 K1 K2 K3 erode Descrip on The Johnson-Holmquist ceramic model (JH-2) is used to model brittle materials having a higher strength in compression than in tension. The yield criterion and flow rule follow J2 plasticity. A bulking pressure term is added to account for dilataion during deviatoric plastic flow. The figure below shows the von Mises yield stress as function of pressure and damage. Damage evolves according to: D˙ = ˙pef f f ail where: IMPETUS Afea Solver v.3.0 87 Material proper es Figure 21: Effective flow stress as a function of pressure and damage ( f ail = D1 T +p pHEL )D2 The elastic pressure-volume relationship is cubic in compression: pelastic = K1 µ + K2 µ2 + K3 µ3 µ > 0 and linear in tension: pelastic = K1 µ µ < 0 where: µ = ρ/ρ0 − 1 It is assumed that a fraction β of the elastic deviatoric strain energy that is being released as damage grows is transformed into pressure (the rest dissipates into heat). This is the so called bulking pressure. Assuming an incremental release of elastic deviatoric strain energy ∆U , the incremental bulking pressure is defined as: ∆pbulk = √ p2 + 2βK1 ∆U − p Here p is the total pressure: p = pelastic + pbulk IMPETUS Afea Solver v.3.0 88 Material proper es *MAT LIBRARY *MAT LIBRARY ”material name”, mid Parameter defini on Variable Description ”material name” mid Unique name as given in Materials library Material ID Descrip on Includes material from Materials library. IMPETUS Afea Solver v.3.0 89 Material proper es *MAT METAL *MAT METAL mid, ρ, E, ν, did, tid cid, ξ, tresca, c, 0 , m, T0 , Tm s0 , s1 Parameter defini on Variable Description mid ρ E ν did tid cid Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID Thermal property command ID ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress versus plastic strain (equivalent measures) Kinematical hardening parameter ranging from 0 to 1 default: 0 (pure iso-tropic hardening) Flag to activate Tresca yield criterion options: 0 → von Mises 1 → Tresca Strain rate hardening parameter default: 0 Reference strain rate default: 1 Thermal softening parameter default: thermal softening deactivated Thermal softening reference temperature default: 0 Melting temperature default: 1.0d20 Damage softening parameter (threshold damage level) default: s0 = 1 Damage softening parameter ξ tresca c 0 m T0 Tm s0 s1 Descrip on This is constitutive model for ductile metals with optional thermal softening and strain rate hardening. The yield stress is defined as: )c ( ( ) ) ( ˙pef f T − T0 m p σy = f (ef f ) · g(D) · 1 − · 1+ Tm − T0 0 where f (pef f ) is a user defined CURVE[/ref] or [ref]FUNCTION, g(D) is an optional damage softening and T is the current temperature. g(D), where D is the damage level, is defined as: IMPETUS Afea Solver v.3.0 90 Material proper es g(D) = 1 D ≤ s0 D − s0 · (s1 − 1) D > s0 1+ 1 − s0 That is, g(D) drops linearly from 1 at D = s0 to s1 at D = 1 (full damage).The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) where K is the bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 91 Material proper es *MAT MOONEY RIVLIN *MAT MOONEY RIVLIN mid, ρ, K C1 , C2 , α1 , β1 , α2 , β2 , α3 , β3 α4 , β4 Parameter defini on Variable Description mid ρ K C1 C2 α1 β1 α2 β2 α3 β3 α4 β4 Unique material identification number Density Bulk modulus Shear stiffness parameter Shear stiffness parameter Viscous stiffness parameter Viscous decay parameter Viscous stiffness parameter Viscous decay parameter Viscous stiffness parameter Viscous decay parameter Viscous stiffness parameter Viscous decay parameter Descrip on This is a visco-elastic model for rubber materials. The total stress σ is the sum of a rate independent elastic stress tensor σe and a viscous deviatoric stress tensor σv . σ = σe + σv It is to be noted that the viscous stresses are not part of the original Mooney-Rivlin material model. The rate independent deviatoric response is non-linear and it is controlled by the two parameters C1 and C2 . The principal stresses are defined as: 2C1 (2λ1 − λ2 − λ3 ) − 3 2C1 σ2 = (2λ2 − λ3 − λ1 ) − 3 2C1 σ3 = (2λ3 − λ1 − λ2 ) − 3 σ1 = 2C2 (2/λ1 − 1/λ2 − 1/λ3 ) − p 3 2C2 (2/λ2 − 1/λ3 − 1/λ1 ) − p 3 2C2 (2/λ3 − 1/λ1 − 1/λ2 ) − p 3 where λi , i = [1, 3] are eigenvalues of Cauchy-Green’s right stretch tensor C = FT F. The corresponding principal directions are ni and the rate independent stress tensor σe can be expressed as: σe = 3 ∑ σi ni ⊗ ni i=1 IMPETUS Afea Solver v.3.0 92 Material proper es The pressure p is a linear function of the volumetric strain v : p = −Kv The viscous stresses σv are purely deviatoric and are controlled by parameters αk and βk , k = [1, 4]. σv (t) = ∫ 4 ∑ 2αk k=1 βk t ˙dev (τ )e(τ −t)/βk dτ 0 Here t is the current time and ˙dev is the deviatoric strain rate. Note that, given a constant deviatoric strain rate ˙dev , the viscous stress response will asymptotically approach: lim σv = t→∞ IMPETUS Afea Solver v.3.0 4 ∑ 2αk ˙dev k=1 93 Material proper es *MAT MULTILAYER ORTHOTROPIC *MAT MULTILAYER ORTHOTROPIC mid, ρ, E1 , E2 , G12 , ν12 E3 , G13 , G23 , ν13 , ν23 , t , c , erode ndir, α1 , ..., α7 c Parameter defini on Variable Description mid ρ E1 E2 G12 ν12 E3 G13 G23 ν13 ν23 t c erode Unique material identification number Density In-plane Young’s modulus (0-direction) In-plane Young’s modulus (othogonally to 0-direction) In-plane shear modulus Poisson’s ratio Young’s modulus in transverse direction Transverse shear modulus Transverse shear modulus Poisson’s ratio Poisson’s ratio Tensile failure strain in fiber direction Compressive failure strain in fiber direction Element erosion flag options: 0 → failed elements keep the bulk stiffness 1 → failed elements are eroded 2 → node splitting Number of fiber directions (up to 7) Fiber directions for failure check (angles relatively the 0-direction) Strain rate sensitivity parameter ndir α1 , ..., α7 c Descrip on This is an orthototropic composite model where failure can occur in up to 7 different fiber directions. The stress can be expressed as: σ = L : + c˙ where L is the tangential stiffness of the material (fourth order tensor). Failure occurs if the tensile or compressive strain in a fiber direction exceeds t and c , respectively. All deviatoric stresses are set to zero at fiber failure. Initial fiber directions need to be defined using either INITIAL MATERIAL DIRECTION[/ref], [ref]INITIAL MATERIAL DIRE or [ref]INITIAL MATERIAL DIRECTION WRAP. IMPETUS Afea Solver v.3.0 94 Material proper es *MAT ORTHOTROPIC *MAT ORTHOTROPIC mid, ρ, E1 , E2 , G12 , ν12 , ν23 c, cdec , Xt , Xc , Yt , Yc , β, S erode, res Parameter defini on Variable Description mid ρ E1 E2 G12 ν12 ν23 c cdec Xt Xc Yt Yc β S erode Unique material identification number Density Young’s modulus in fiber direction Young’s modulus orthogonally to fiber direction In-plane shear modulus Poisson’s ratio Poisson’s ratio Strain rate sensitivity parameter Strain rate sensitivity decay coefficient Ultimate tensile stress in fiber direction Ultimate compressive stress in fiber direction Ultimate tensile stress orthogonally to fiber direction Ultimate compressive stress orthogonally to fiber direction Failure parameter Failure parameter Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded Residual strength after failure default: 0 res Descrip on This is an orthototropic composite model. The stress can be expressed as: ∫ t c σ =L:+ (τ ˙ ) · e(τ −t)/cdec dτ cdec 0 where L is the tangential stiffness of the material (fourth order tensor). There are four different failure criteria. Fiber tension/shear if σ11 > 0: D1 = (σ11 /Xt )2 + β(|τ12 |/S) Fiber compression if σ11 < 0: IMPETUS Afea Solver v.3.0 95 Material proper es D2 = (σ11 /Xc )2 Matrix tension if σ22 > 0: D3 = (σ22 /Yt )2 + β(|τ12 |/S) Matrix compression/shear if σ22 < 0: D4 = (σ11 /Xc )2 + ((Yc /2S)2 − 1)(σ22 /Yc ) + (τ12 /S)2 All stresses are reduced with the factor res at fiber failure, i.e. if D1 ≥ 1. D2 ≥ 1 indicates fiber buckling whereby compressive fiber stresses (σ11 ) and in plane shear stresses (τ12 ) are reduced with the factor res. D3 ≥ 1 or D4 ≥ 1 indicates matrix failure and σ22 and τ12 are reduced with the factor res. Initial fiber directions need to be defined using either INITIAL MATERIAL DIRECTION[/ref], [ref]INITIAL MATERIAL DIRE or [ref]INITIAL MATERIAL DIRECTION WRAP. IMPETUS Afea Solver v.3.0 96 Material proper es *MAT PWL *MAT PWL Descrip on Has been renamed to MAT METAL. IMPETUS Afea Solver v.3.0 97 Material proper es *MAT RIGID *MAT RIGID mid, ρ Parameter defini on Variable Description mid ρ Unique material identification number Density Descrip on Rigid material. IMPETUS Afea Solver v.3.0 98 Material proper es *MAT USER JS *MAT USER JS mid, ρ, E, ν cmat7 , ... , cmat14 cmat15 , ... , cmat22 cmat23 , ... , cmat30 cmat31 , ... , cmat38 cmat39 , ... , cmat46 cmat47 , ... , cmat54 cmat55 , ... , cmat62 Parameter defini on Variable Description mid ρ E ν cmat7 , ... cmat15 , cmat22 cmat23 , cmat30 cmat31 , cmat38 cmat39 , cmat46 cmat47 , cmat54 cmat55 , cmat62 , cmat14 ... , Unique material identification number Density Young’s modulus Poisson’s ratio Custom material properties Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties Descrip on User defined material model in javascript. IMPETUS Afea Solver v.3.0 99 Material proper es *MAT USER X *MAT USER X mid, ρ, E, ν cmat7 , ... , cmat14 cmat15 , ... , cmat22 cmat23 , ... , cmat30 cmat31 , ... , cmat38 cmat39 , ... , cmat46 cmat47 , ... , cmat54 cmat55 , ... , cmat62 Parameter defini on Variable Description mid ρ E ν cmat7 , ... cmat15 , cmat22 cmat23 , cmat30 cmat31 , cmat38 cmat39 , cmat46 cmat47 , cmat54 cmat55 , cmat62 , cmat14 ... , Unique material identification number Density Young’s modulus Poisson’s ratio Custom material properties Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties ... , Custom material properties Descrip on User defined material model for fortran compiled DLL. IMPETUS Afea Solver v.3.0 100 Material proper es *MAT VISCO PLASTIC *MAT VISCO PLASTIC mid, ρ, E, ν, did, tid σ0 , Q1 , C1 , Q2 , C2 , cid, cdec , α β, m, T0 , Tm Parameter defini on Variable Description mid ρ E ν did tid σ0 Q1 C1 Q2 C2 cid cdec α β m T0 Tm Unique material identification number Density Young’s modulus Poisson’s ratio Damage property command ID Thermal property command ID Initial yield stress Voce hardening coefficient Voce hardening coefficient Voce hardening coefficient Voce hardening coefficient ID of a FUNCTION[/ref] or [ref]CURVE defining the viscosity of the material Viscous stress decay coefficient Non-linear elastic stifness coefficient Plastic flow stress triaxiality factor Thermal softening parameter Thermal softening reference temperature Thermal softening melting temperature Descrip on This is a non-linear visco-plastic constitutive model where the total stress σ is the sum of three terms: σ = σ1 + σ2 + σ3 σ 1 is a non-linear viscous stress, σ 2 is a non-linear elastic stress and σ 3 is a linear elastic stress component. The rheological model is depicted below. The non-linear viscous stress σ 1 is defined as: σ 1 = f (�˙ , ) · �˙ where f is a user defined FUNCTION[/ref] or [ref]CURVE with ID cid. FUNCTION allows the viscosity to depend on both the effective geometric strain and the strain rate. If using a CURVE, the viscosity is a function of ¯˙ only. ¯˙ is a smeared out strain rate measure: IMPETUS Afea Solver v.3.0 101 Material proper es Figure 22: Rheological model for MAT VISCO PLASTIC 1 _ � (t) = cdec ∫ t (τ ˙ )e−τ /cdec dτ 0 Note that ¯˙ = ˙ if cdec = 0. The non-linear elastic stress σ 2 is defined to grow quadratically with the total deviatoric strain dev : ( 2 σ = 2αG 2 dev : dev 3 )1/2 · dev G is the linear shear modulus. The linear elastic stress component σ 3 is defined as: σ 3 = −pI + 2Gedev p is the hydrostatic pressure and edev is the deviatoric part of the linear elastic strain tensor e in the relation: = e + p where p is a plastic strain tensor. The plasticity model is based on a von Mises effective stress definition and an iso-choric plastic flow law. The plastic yield stress is defined as: [ ] [ ] [ ] 2 ∑ T − T0 m βp −Ci pef f σy = σ0 + Qi (1 − e ) · 1− · 1+ Tm − T0 σ0 i=1 Note that β 6= 0 leads to a pressure dependent yield stress. β 6= 0 and an iso-choric plastic flow makes the flow rule non-associated. The hydrostatic pressure p is defined as: p = −Kv + 3KαT (T − Tref ) IMPETUS Afea Solver v.3.0 102 Material proper es where K is the linear bulk modulus, v is the volumetric strain. αT is the thermal expansion coefficient and Tref is the reference temperature (see PROP THERMAL). IMPETUS Afea Solver v.3.0 103 Material proper es *PROP DAMAGE BRITTLE *PROP DAMAGE BRITTLE did, erode, noic σs , Kc , ts , αs Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Threshold stress (maximum principal stress) for initiation of fracture. Stress intensity factor for crack propagation (only used with node splitting) default: not used Time to initiate fracture at threshold stress default: not used Exponent controlling time to initiate fracture default: not used noic σs Kc ts αs Descrip on This is a brittle fracture criterion. The material cracks once the damage parameter, D, has evolved from 0 to 1. The damage is defined as: ∫ 1 t D= (σ1 /σs )αs dt ts 0 where σ1 is the maximum principal stress. Note that the damage only grows if σ1 ≥ σs . Crack propagation is controlled by a stress intensity criterion (if having node splitting activated). The stress intensity KI is estimated for the integration points surrounding the crack tip. The crack will propagate if KI > Kc (Modus I crack). IMPETUS Afea Solver v.3.0 104 Material proper es *PROP DAMAGE CL *PROP DAMAGE CL did, erode, noic Wc , GI , σs , ts , αs Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Damage parameter. If referring to a function (see FUNCTION STATIC) the damage parameter can be defined to depend on the location options: constant, fcn Fracture energy parameter (only used with node splitting) default: not used Spall strength (threshold stress) default: not used Time to develop spall fracture at threshold stress default: not used Exponent controlling time to develop spall fracture default: not used noic Wc GI σs ts αs Descrip on This is the Cockcroft-Latham failure criterion. It has been complemented with a tensile fracture/spalling crierion. The material will lose its shear strength once the damage parameter, D, has evolved from 0 to 1. The damage is defined as: D= 1 Wc ∫ pef f 0 max(0, σ1 )dpef f + 1 ts ∫ t (σ1 /σs )αs dt 0 where σ1 is the maximum principal stress. Note that the tensile fracture/spalling term only contributes to the damage growth if σ1 ≥ σs . IMPETUS Afea Solver v.3.0 105 Material proper es *PROP DAMAGE CL ANISOTROPIC *PROP DAMAGE CL ANISOTROPIC did, erode, noic W0 , W90 , Wt Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Damage parameter for the rolling/extrusion direction Damage parameter for the transverse direction Damage parameter for the material thickness direction noic W0 W90 Wt Descrip on This is an anisotropic Cockcroft-Latham like failure criterion. The material will fail once the damage parameter, D, has evolved from 0 to 1. ∫ D= 0 pef f max(0, σ1 ) p def f Wc where σ1 is the maximum principal stress. Wc is a weighted ductility parameter and it depends on the loading direction: √ 2 cos2 α + W 2 cos2 α Wc = W02 cos2 α0 + W90 90 t t α0 , α90 and αt are the angles between the maximum principle stress and the material rolling/extrusion, transverse and thickness directions, respectively. The initial material orientation is defined using either INITIAL MATERIAL DIRECTION[/ref], [ref]INITIAL MATERIAL DIRE or [ref]INITIAL MATERIAL DIRECTION WRAP. IMPETUS Afea Solver v.3.0 106 Material proper es *PROP DAMAGE IMP *PROP DAMAGE IMP did, erode, noic Wc , n Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Damage parameter Damage growth exponent noic Wc n Descrip on IMPETUS failure criterion is similar to the Cockcroft-Latham failure criterion. However, it has been equipped with one extra parameter n that allows for an anisotropic damage growth. The model is based on the assumption that defects deform with the material. It is further assumed that compressed defects exposed to tensile loading are more harmful than elongated defects. The damage growth is assumed proportional to the maximum eigenvalue σ ˆ1 of a distorted stress tensor σ ˆ. 1 D= Wc ∫ pef f 0 max(0, σ ˆ1 )dpef f The distorted stress tensor σ ˆ is formed as: σ ˆ = AσA where σ is the current stress tensor and A is a symmetric tensor describing the defect compression. A is a function of the principal stretches (λ1 , λ2 , λ3 ) and of their corresponding eigenvectors (v1 , v2 , v3 ). A= ) 3 ( ∑ λ1 n i=1 λi vi ⊗ vi Note that λ1 is the maximum principal stretch. The formulation ensures that the damage growth is equivialent to Cockcroft-Latham in proportional loading where λ1 coincides with σ1 . IMPETUS Afea Solver v.3.0 107 Material proper es *PROP DAMAGE IMP ISO *PROP DAMAGE IMP ISO did, erode, noic Aimp , Bimp , Wimp Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Damage parameter Damage parameter Damage parameter noic Aimp Bimp Wimp Descrip on This is the IMPETUS isotropic failure criterion. The material will lose its shear strength pressure once the damage parameter, D, has evolved from 0 to 1. The damage is defined as: ] [ ∫ p ef f 1 p p Aimp max(0, σ1 )def f + Bimp σ1 ef f D= Wimp 0 where σ1 is the maximum principal stress. IMPETUS Afea Solver v.3.0 108 Material proper es *PROP DAMAGE JC *PROP DAMAGE JC did, erode, noic d1 , d2 , d3 , d4 , d5 , 0 , T0 , Tm Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Damage parameters Reference strain rate default: 1 Reference and melting temperatures noic d1 , d2 , d3 , d4 , d5 0 T0 , Tm Descrip on This is the Johnson-Cook failure criterion. The material will lose its shear strength pressure once the damage parameter, D, has evolved from 0 to 1. The damage growth rate is defined as: D˙ = ˙pef f f where: |d3 | p f = (d1 + d2 · e σef f ) · (1 + d4 · ln( ˙pef f 0 )) · (1 + d5 · ( T − T0 )) Tm − T0 and: p = −(σxx + σyy + σzz )/3 IMPETUS Afea Solver v.3.0 109 Material proper es *PROP DAMAGE STRAIN *PROP DAMAGE STRAIN did, erode, noic t c vol geo f ail , f ail , f ail , f ail Parameter defini on Variable Description did erode Unique damage identification number Element erosion flag options: 0 → failed element is not eroded 1 → failed element is eroded 2 → node splitting at failure (crack plane orthogonal to max principal strain) 3 → node splitting at failure (crack plane orthogonal max principal stress) Flag to turn off cracking along interface between different materials options: 0 → material interface cracks are allowed 1 → material interface cracks are not allowed Effective geometrical failure strain default: not active Tensile failure strain default: not active Compressive failure strain default: not active Volumetric failure strain default: not active noic geo f ail tf ail cf ail vol f ail Descrip on Various strain failure criteria. The material will lose its shear strength pressure once at least one of the criteria is met. The effective geometrical strain definition is: √ 2 geo = : 3 IMPETUS Afea Solver v.3.0 110 Material proper es *PROP THERMAL *PROP THERMAL tid, αT , Cp , λ, k, Tref Parameter defini on Variable Description tid αT Cp λ k Unique thermal property identification number Heat expansion coefficient Heat capacity Heat conductivity Plastic work heat conversion factor default: 0.9 Reference temperature for thermal expansion Tref Descrip on Thermal property command. It is to be referenced from a material command. IMPETUS Afea Solver v.3.0 111 Ini al condi ons Ini al condi ons *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL *INITIAL DAMAGE RANDOM DAMAGE SURFACE RANDOM MATERIAL DIRECTION MATERIAL DIRECTION VECTOR MATERIAL DIRECTION WRAP STATE STATE HAZ STATE WELDSIM STRESS FUNCTION TEMPERATURE VELOCITY IMPETUS Afea Solver v.3.0 112 Ini al condi ons *INITIAL DAMAGE RANDOM *INITIAL DAMAGE RANDOM entype, enid, a, b, Dmax , R, cid Parameter defini on Variable Description entype Entity type options: M, P, PS Entity ID Defect distribution parameter Defect distribution parameter Maximum initial damage Optional imperfection radius ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress (sigy0) as function of initial damage default: not used enid a b Dmax R cid Descrip on This command is used to define a randomly distributed initial damage. A distribution function f (D) describes the number of defects per unit volume of matter. { a · e−bD D ≤ Dmax f (D) = 0 D > Dmax Note that the maximum initial damage cannot be larger than Dmax . The number of defects N per unit volume of matter in the range D0 to Dmax can be calculated by integrating f (D) from D0 to Dmax : ∫ Dmax N= f (D)dD D0 Based on the assumed damage distribution f (D) one can show that the probability p of having at least one initial defect larger than or equal to D0 in a volume v is: p = 1 − e−N ·v This probability expression can be used to assign an initial damage level to to each integration point in the model. The damage level is obtained by solving the expression for D0 (given a random number p and an integration point volume v). IMPETUS Afea Solver v.3.0 113 Ini al condi ons *INITIAL DAMAGE SURFACE RANDOM *INITIAL DAMAGE SURFACE RANDOM entype, enid, ∆0 , m, Dmax , R, cid Parameter defini on Variable Description entype Entity type options: M, P, PS Entity ID Defect distribution parameter Defect distribution parameter Maximum initial damage Optional imperfection radius ID of a CURVE[/ref] or [ref]FUNCTION defining yield stress (sigy0) as function of initial damage default: not used enid ∆0 m Dmax R cid Descrip on This command is used to define randomly distributed initial defects on the surface of a body. The defects are interpreted as equivalent to an initial damage D. The probability P of having an initial defect larger or equal to D on a surface A is defined as: 1 [ ( ) ] : D=0 1−D m P (A, D) = 1 − exp −A : 0 < D ≤ Dmax ∆0 0 : D > Dmax The variables ∆0 , m and Dmax are input parameters that typically need to be tuned to match experimental data with a certain spread. The inverse function D(A, P ) is used to define the intitial damage level for each integration point near the material surface. In this context 0 ≤ P ≤ 1 is a random number and A is the area represented by the integration point. 0 D(A, P ) = IMPETUS Afea Solver v.3.0 1 − ∆0 Dmax ( −ln(1 − P ) A )1/m : P > P (A, 0) : P (A, Dmax ) < P ≤ P (A, 0) : P < P (A, Dmax ) 114 Ini al condi ons Figure 23: Typical initial damage probability function P (A, D) - ∆0 = 0.15, m = 6, Dmax = 0.4, A = 2.0e − 5 Figure 24: Typical initial damage function D(A, P ) - ∆0 = 0.15, m = 6, Dmax = 0.4, A = 2.0e − 5 IMPETUS Afea Solver v.3.0 115 Ini al condi ons *INITIAL MATERIAL DIRECTION *INITIAL MATERIAL DIRECTION nid, x ˆx , x ˆy , x ˆz , y¯x , y¯y , y¯z Parameter defini on Variable Description nid x ˆx , x ˆy , x ˆz y¯x , y¯y , y¯z Node ID Direction of local x-axis Vector needed for the definition of the local y- and z-axis Descrip on This command is used to define local material directions. Data is input for the element corner nodes. The local directions at the element integration points at time 0 are interpolated from the element corner node values. The local y-axis (ˆy) and z-axis (ˆz) are defined as: ˆz = ˆx × ¯y |ˆx × ¯y| ˆy = ˆz × ˆx Alternative commands for definitions of local material directions are INITIAL MATERIAL DIRECTION VECTOR[/ref] and [ref]INITIAL MATERIAL DIRECTION WRAP. IMPETUS Afea Solver v.3.0 116 Ini al condi ons *INITIAL MATERIAL DIRECTION VECTOR *INITIAL MATERIAL DIRECTION VECTOR coid, entype, enid x ˆx , x ˆy , x ˆz , y¯x , y¯y , y¯z Parameter defini on Variable Description coid entype Command ID Entity type options: P, PS Entity ID Direction of local x-axis Optional vector used for the definition of the local y- and z-axis enid x ˆx , x ˆy , x ˆz y¯x , y¯y , y¯z Descrip on This command is used to define local material directions. If ¯y = (¯ yx , y¯y , y¯z ) has been defined the local and z-axis (¯z) is computed as: ˆz = ˆx × ¯y |ˆx × ¯y| If ¯y has not been defined the local z-axis (¯z) is equivalent to: ˆ ˆz = n ˆ is the local element face normal. Note that this option only works if the structure is modeled with where n one single element in its thickness direction. Once ˆz has been computed ˆy is calculated as: ˆy = ˆz × ˆx All direction parameters can either be constants or defined as functions of the local coordinate (x, y, z). IMPETUS Afea Solver v.3.0 117 Ini al condi ons *INITIAL MATERIAL DIRECTION WRAP *INITIAL MATERIAL DIRECTION WRAP coid, entype, enid x 0 , y0 , z 0 , u ˆx , u ˆy , u ˆz , α Parameter defini on Variable Description coid entype Command ID Entity type options: P, PS Entity ID Coordinate used for definition of the ply location Vector used for definition of the ply orientation Angle used for definition of fiber direction enid x0 , y0 , z0 u ˆx , u ˆy , u ˆz α Descrip on This command is used to define local material directions in fiber composites. The user defines the location and orientation of a ”ply” in space. This ply is then wrapped around the component. The ply first needs to be projected onto/wrapped around the component. This projection generates intermediate in-plane directions ¯x and ¯y. ¯y = ˆ ˆz × u ˆ| |ˆz × u ¯x = ¯y × ˆz where ˆz is the local face surface normal direction. The local fiber direction ˆx and the orthogonal direction ˆy can now be defined by rotating the intermediate directions with the angle α. ˆx = cos(α)¯x + sin(α)¯y ˆy = − sin(α)¯x + cos(α)¯y IMPETUS Afea Solver v.3.0 118 Ini al condi ons Figure 25: Definition of fiber direction IMPETUS Afea Solver v.3.0 119 Ini al condi ons *INITIAL STATE *INITIAL STATE eid, etype, ip, mtype, V0 F11 , F12 , F13 F21 , F22 , F23 F31 , F32 , F33 σ11 , σ22 , σ33 , σ12 , σ23 , σ31 11 , 22 , 33 , 12 , 23 , 31 v01 , ..., v08 v09 , ..., v16 v17 , ..., v24 Parameter defini on Variable Description eid etype ip mtype V0 F11 , F12 , F13 F21 , F22 , F23 F31 , F32 , F33 σ11 , σ22 , σ33 σ12 , σ23 , σ31 11 , 22 , 33 12 , 23 , 31 v01 , ..., v08 v09 , ..., v16 v17 , ..., v24 Element ID Element type Integration point number Material type Integration point volume in undeformed state Deformation gradient components Deformation gradient components Deformation gradient components Stress components Strain components State variables 1-8 State variables 9-16 State variables 17-24 Descrip on Definition of the initial state (deformation, stresses and state variables) on integration point level. This command is used by the solver when writing a state file (impetus stateX.k and impetus stateX.bin) with the complete state for a set of parts defined in the input deck (see parameter resid in OUTPUT). IMPETUS Afea Solver v.3.0 120 Ini al condi ons *INITIAL STATE HAZ *INITIAL STATE HAZ entypeweld , enidweld , entypebase , enidbase , cidsigy , cidD0 Parameter defini on Variable Description entypeweld Weld entity type options: P, PS Weld entity ID Base material entity type options: P, PS Base material entity ID ID of a CURVE[/ref] or [ref]FUNCTION describing yield stress as function of the distance from the weld default: not used ID of a CURVE[/ref] or [ref]FUNCTION describing initial damage as function of the distance from the weld default: not used enidweld entypebase enidbase cidsigy cidD0 Descrip on This command is used to define mechanical properties in a HAZ after a welding operation. Initial yield stress and damage are defined as functions of the distance from the weld. The yield stress can be accessed in FUNCTION through the built in variable sigy0. IMPETUS Afea Solver v.3.0 121 Ini al condi ons *INITIAL STATE WELDSIM *INITIAL STATE WELDSIM type, sf1 , ..., sf6 nid1 , v1 , ..., v6 . nidn , v1 , ..., v6 Parameter defini on Variable Description type Input type options: 1 → initial yield stress is imported from WeldSim (TM) Scale factors Node identification number Node quantities Node identification number Node quantities sf1 , ..., sf6 nid1 v1 , ..., v6 nidn v1 , ..., v6 Descrip on This command allows the user to import simulation results from WeldSim (TM), in order to define the distribution of material properties in the heat affected zone (HAZ) after a welding operation. The GUI of IMPETUS Afea Solver can read and visualize result data from WeldSim (TM) and export it to a format that can be handled by IMPETUS Afea Solver for further computational analysis. Currently only the yield stress can be imported (type=1). The yield stress can be accessed in FUNCTION through the built in variable sigy0. IMPETUS Afea Solver v.3.0 122 Ini al condi ons *INITIAL STRESS FUNCTION *INITIAL STRESS FUNCTION entype, enid, fidxx , fidyy , fidzz , fidxy , fidyz , fidzx multi Parameter defini on Variable Description entype Entity type options: M, P, PS Entity ID ID of FUNCTION defining σxx as function of (x, y, z) ID of FUNCTION defining σyy as function of (x, y, z) ID of FUNCTION defining σzz as function of (x, y, z) ID of FUNCTION defining σxy as function of (x, y, z) ID of FUNCTION defining σyz as function of (x, y, z) ID of FUNCTION defining σzx as function of (x, y, z) Treatment of multiple commands options: 0 → stresses from previous commands are overwritten 1 → stresses from multiple commands are superposed 2 → stress component with largest absolute value is kept enid fidxx fidyy fidzz fidxy fidyz fidzx multi Descrip on Definition of initial stresses. IMPETUS Afea Solver v.3.0 123 Ini al condi ons *INITIAL TEMPERATURE *INITIAL TEMPERATURE entype, enid, fid Parameter defini on Variable Description entype Entity type options: P, PS Entity identification number ID of a FUNCTION defining the temperature field enid fid Descrip on Definition of an initial temperature field. IMPETUS Afea Solver v.3.0 124 Ini al condi ons *INITIAL VELOCITY *INITIAL VELOCITY entype, enid, vx0 , vy0 , vz0 , ωx , ωy , ωz x0 , y0 , z0 , δvx , δvy , δvz Parameter defini on Variable Description entype Entity type options: N, NS, P, PS, ALL, G Entity identification number Initial velocity in x-direction default: 0 Initial velocity in y-direction default: 0 Initial velocity in z-direction default: 0 Initial angular velocity vector default: (0,0,0) Center of rotation default: (0,0,0) Gradient of velocity field default: (0,0,0) enid vx0 vy0 vz0 ωx , ωy , ωz x0 , y0 , z0 δvx , δvy , δvz Descrip on This command is used to define initial velocities and initial angular velocities, applying to nodes and to soil particles (see PBLAST). The command is additive and multiple velocity definitions are summed up to form a total velocity. An initial velocity term of a node or a soil particle at coordinate (x, y, z) is defined as: vx vx0 x − x0 ωx δvx (x − x0 ) vy vy0 y − y0 ωy δvy (y − y0 ) = + × + vz vz0 z − z0 ωz δvz (z − z0 ) IMPETUS Afea Solver v.3.0 125 Boundary condi ons Boundary condi ons *BC MOTION *BC SYMMETRY *BC TEMPERATURE IMPETUS Afea Solver v.3.0 126 Boundary condi ons *BC MOTION *BC MOTION coid entype, enid, bctr , bcrot , csysidtr , csysidrot , tbeg , tend pmeth1 , direc1 , cid1 , sf1 . pmethn , direcn , cidn , sfn Parameter defini on Variable Description coid entype Command ID (optional) Entity type options: N, NS, P, PS, ALL, G Entity identification number Translational constraints options: 0, X, Y, Z, XY, YZ, ZX, XYZ Rotational constraint options: 0, X, Y, Z, XY, YZ, ZX, XYZ Coordinate system ID for translational constraints Coordinate system ID for rotational constraints (negative or 0 for rotation around COG) Activation time Termination time Method used to prescribe motion (acceleration/velocity or displacement) options: A, V, D Direction of precsribed motion options: X, Y, Z, RX, RY, RZ ID of a CURVE[/ref] or [ref]FUNCTION defining prescribed motion Scale factor for curve ordinate values default: 1 Method used to prescribe motion (acceleration/velocity or displacement) options: A, V, D Direction of precsribed motion options: X, Y, Z, RX, RY, RZ ID of a CURVE[/ref] or [ref]FUNCTION defining prescribed motion Scale factor for curve ordinate values default: 1 enid bctr bcrot csysidtr csysidrot tbeg tend pmeth1 direc1 cid1 sf1 pmethn direcn cidn sfn Descrip on Definition of kinematic boundary conditions. When referring to a local cylindrical coordinate system (csystr), X corresponds to the radial direction, Y to the tangential direction and Z to the axial direction. IMPETUS Afea Solver v.3.0 127 Boundary condi ons *BC SYMMETRY *BC SYMMETRY plane, csysid1 , csysid2 , csysid3 , tol Parameter defini on Variable Description plane Symmetry planes through the origin options: X, Y, Z, XY, YZ, ZX, XYZ IDs of coordinate systems that define up to 3 different symmetry planes (only active if plane=0) maximum distance between a node and the symmetry plane for symmetry conditions to be applied csysid1 , csysid3 tol csysid2 , Descrip on This command defines up to three symmetry planes at x, y or z = 0 or at the origin of specified coordinate systems. When referring to a local coordinate system, the symmetry plane normal is defined as the local xdirection of the coordinate system. The normal direction of the nearest element face is taken as symmetry plane normal in case the local x-direction has not been explicitly defined in the coordinate system command. Appropriate boundary conditions are automatical applied to nodes located on a symmetry plane. External faces on a symmetry plane are excluded from the contact. Symmetry conditions are also applied to the boundary of global PBLAST domains. Symmetry planes can also be used as rigid frictionless walls, that nodes can not penetrate. IMPETUS Afea Solver v.3.0 128 Boundary condi ons *BC TEMPERATURE *BC TEMPERATURE entype, enid, cid, sf , tbeg , tend Parameter defini on Variable Description entype Entity type options: P, PS Entity identification number ID of a CURVE[/ref] or [ref]FUNCTION defining temperature versus time Temperature curve scale factor default: 1 Start time default: 0 End time default: 1.0e10 enid cid sf tbeg tend Descrip on Definition of temperature boundary condition. Note that the temperature is computed and stored directly at the integration points. IMPETUS Afea Solver v.3.0 129 Loads Loads *LOAD CENTRIFUGAL *LOAD DAMPING *LOAD FORCE *LOAD GRAVITY *LOAD PRESSURE *LOAD SHEAR *LOAD THERMAL BODY *LOAD THERMAL SURFACE *PRESTRESS BOLT IMPETUS Afea Solver v.3.0 130 Loads *LOAD CENTRIFUGAL *LOAD CENTRIFUGAL entype, enid, cid, csysid, tbeg , tend Parameter defini on Variable Description entype Entity type options: N, NS, P, PS Entity identification number ID of a CURVE[/ref] or [ref]FUNCTION defining angular velocity versus time Local coordinate system ID Start time End time default: 1.0e10 enid cid csysid tbeg tend Descrip on This command is used to apply centrifugal forces on a component without actually spinning the model. The command is typically used to initialize stresses in a rotating fan blade. The local coordinate system is used to define the center of rotation and the rotational axis (local x-axis). IMPETUS Afea Solver v.3.0 131 Loads *LOAD DAMPING *LOAD DAMPING entype, enid, cid, µ, cdec Parameter defini on Variable Description entype Entity type options: N, NS, P, PS, ALL Entity ID ID of a CURVE[/ref] or [ref]FUNCTION defining the mass damping coefficient C versus time Viscous damping coefficient Viscous decay coefficient enid cid µ cdec Descrip on This command is used to define mass damping and viscous damping for a given subset of the model. The mass damping force Fi acting a node i is defined as: Fi = −C · mi · vi where C is the damping coefficient defined by the CURVE[/ref] or [ref]FUNCTION with ID cid, mi is the node mass and vi is the node velocity. The viscous damping is defined as an artificial material viscosity. This viscosity produces an extra, strain rate dependent, stress term σµ : ∫ t µ (τ ˙ ) · e(τ −t)/cdec dτ σµ = cdec 0 IMPETUS Afea Solver v.3.0 132 Loads *LOAD FORCE *LOAD FORCE entype, enid, direc, cid, sf , csysid, tbeg , tend Parameter defini on Variable Description entype Entity type (P only for rigid bodies) options: N, NS, G, FS, P Entity identification number Force/moment direction options: X, Y, Z, RX, RY, RZ ID of a CURVE[/ref] or [ref]FUNCTION defining force/moment versus time Force/moment scale factor default: 1 Local coordinate system ID default: global coordinates are used Start time End time default: 1.0e10 enid direc cid sf csysid tbeg tend Descrip on This command is used to apply external forces to a node, to a set of nodes or to a rigid body. If the force is distributed to more than one node (entype = NS, G or FS), the contribution to each node is proportional to the node mass. That is, the force applied to a node i is: Fi = mi Ftot mtot where mtot is the total mass of all nodes in the set and Ftot is the total force. IMPETUS Afea Solver v.3.0 133 Loads *LOAD GRAVITY *LOAD GRAVITY direc, cid, addmass, csysid Parameter defini on Variable Description direc Direction for gravity loading options: X, Y, Z ID of a CURVE[/ref] or [ref]FUNCTION defining gravity coefficient versus time Exclude added mass due to mass scaling from gravity loading options: 0 → include added mass 1 → exclude added mass Optional local coordinate system ID cid addmass csysid Descrip on Defines gravity loading that acts on the full model. It is to be noted that a positive gravity constant results in body forces acting in the negative coordinate axis direction. IMPETUS Afea Solver v.3.0 134 Loads *LOAD PRESSURE *LOAD PRESSURE entype, enid, cid, sf , tbeg , tend , csysid Parameter defini on Variable Description entype Entity type options: P, PS, G, GS, FS Entity identification number ID of a CURVE[/ref] or or [ref]FUNCTION defining pressure versus time Pressure curve scale factor default: 1 Start time default: 0 End time default: 1.0e10 Optional coordinate system ID. If defined, only surfaces visible from its origin are exposed to the pressure load default: not used enid cid sf tbeg tend csysid Descrip on Definition of pressure boundary condition. IMPETUS Afea Solver v.3.0 135 Loads *LOAD SHEAR *LOAD SHEAR entype, enid, cidτ , cidvx , cidvy , cidvz , tbeg , tend Parameter defini on Variable Description entype Entity type options: P, PS, FS Entity identification number ID of a CURVE[/ref] or [ref]FUNCTION ID of a CURVE[/ref] or [ref]FUNCTION ID of a CURVE[/ref] or [ref]FUNCTION ID of a CURVE[/ref] or [ref]FUNCTION Start time default: 0 End time default: 1.0e10 enid cidτ cidvx cidvy cidvz tbeg tend defining defining defining defining the shear traction reference velocity in x-direction reference velocity in y-direction reference velocity in z-direction Descrip on This command defines shear traction on a surface. It can be used to model drag forces and prescribed friction loads. The local direction of the traction ˆt is in that of the reference velocity vref vector minus the local velocity vector v(x), projected onto the surface. ˆt = ˆ⊗n ˆ)(vref − v) (I − n ˆ⊗n ˆ)(vref − v)k k(I − n ˆ=n ˆ(x) is the local surface normal direction. Here n IMPETUS Afea Solver v.3.0 136 Loads *LOAD THERMAL BODY *LOAD THERMAL BODY coid, entype, enid, cid1 , sf , tbeg , tend , cid2 Parameter defini on Variable Description coid entype Command ID Entity type options: P, PS, ALL Entity identification number ID of a CURVE[/ref] or [ref]FUNCTION f1 defining the thermal body load versus time (power/unit volume) Curve scale factor default: 1 Start time End time default: 1.0e20 ID of an optional CURVE[/ref] or [ref]FUNCTION f2 defining the total thermal body load versus time (power) enid cid1 sf tbeg tend cid2 Descrip on This command is used to apply a thermal body load (power per unit volume). f2 is an optional CURVE[/ref] or [ref]FUNCTION describing the exact total power of the heat source. It is needed in situations where the heat source described by f1 (power/unit volume) is partially outside the body where the energy is to be deposited. The magnitude of f1 is then scaled with a factor α in order to match the specified total power in f2 . ∫ α f1 (x, t)dV = f2 (t) V V is the body volume, x is a spatial coordinate and t is the time. Hence, the heat power per unit volume p deposited at a location x becomes: p = α · f1 (x, t) IMPETUS Afea Solver v.3.0 137 Loads *LOAD THERMAL SURFACE *LOAD THERMAL SURFACE coid, entype, enid, cid, sf , tbeg , tend Parameter defini on Variable Description coid entype Command ID Entity type options: FS, G, GS, P, PS, ALL Entity identification number ID of a CURVE[/ref] or [ref]FUNCTION defining the thermal surface load versus time (power/unit area) Curve scale factor default: 1 Start time End time default: 1.0e20 enid cid sf tbeg tend Descrip on This command is used to apply a thermal surface load (power per unit area). IMPETUS Afea Solver v.3.0 138 Loads *PRESTRESS BOLT *PRESTRESS BOLT pidbolt , pidnut , cid, sf , tbeg , tend Parameter defini on Variable Description pidbolt pidnut cid sf Bolt part ID Nut part ID ID of a CURVE[/ref] or [ref]FUNCTION defining bolt shaft stress versus time Shaft stress curve scale factor default: 1 Start time End time default: 1.0e20 tbeg tend Descrip on This command is used to prestress a set of bolts and to apply balancing forces to the corresponding nuts. pid bolt is assumed to contain one or several bolts. pid nut must contain the same number of nuts. The function identifies the discrete bolts and nuts and creates bolt-nut pairs. The bolt shafts are prestressed with the axial stress defined by curve cid. IMPETUS Afea Solver v.3.0 139 Contact and ed interfaces Contact and ed interfaces *CONTACT *CONTACT SUPER *MERGE *MERGE FAILURE COHESIVE *MERGE FAILURE FORCE IMPETUS Afea Solver v.3.0 140 Contact and ed interfaces *CONTACT *CONTACT coid entypes , enids , entypem , enidm , µ, pf ac, tbeg , tend erode, ξ, gids , gidm , δof f set , δmax , αedge , merge fidswear , fidmwear , fidthermal Parameter defini on Variable Description coid entypes Contact command ID Slave entity type options: P, PS, ALL Slave entity identification number Master entity type options: P, PS, ALL Master entity identification number Coulomb coefficient of friction or FUNCTION (see example below) options: constant, fcn default: 0 Penalty factor options: = 0 → automatic calculation of stiffness 6= 0 → | pfac | is the contact pressure per unit penetration distance (rec. option) Contact start time default: 0 Contact end time default: 1.0e10 Flag to update contact surface as elements erode or when creating new free surfaces through node splitting options: 0 → contact surface is not updated 1 → contact surface is updated as new free surfaces are created 2 → contact surface is updated as new free surfaces are created + each node can be in contact with more than one face at a time Fraction of critical damping default: 0.05 ID of a GEOMETRY that defines a sub-space of slave nodes default: no geometry ID of a GEOMETRY that defines a sub-space of master faces default: no geometry Maxmimum penetration offset for nodes that are in contact at time zero. The offset is used to prevent unwanted contact forces default: 0 Max initial penetration that is allowed. Nodes penetrating more than δof f set + δmax are released default: 0 enids entypem enidm µ pf ac tbeg tend erode ξ gids gidm δof f set δmax IMPETUS Afea Solver v.3.0 141 Contact and ed interfaces αedge merge fidswear fidmwear fidthermal Edge-to-edge contact activation angle. An edge between two faces is active in edge-toedge contact if the angle between the face normals is larger than αedge default: 360 Flag to deactivate merged slave nodes from the contact options: 0 → merged nodes are active 1 → merged nodes are inactive ID of a FUNCTION defining the contact wear rate of the slave surface default: no wear calculation ID of a FUNCTION defining the contact wear rate of the master surface default: no wear calculation ID of a FUNCTION defining the thermal contact conductivity default: no contact heat transfer Descrip on Penalty based node-to-surface contact algorithm. Both (slave) nodes and (master) faces are defined from parts or part sets. The contact command ID is needed when referring to a contact force in FUNCTION. It is otherwise optional. It is recommended to work with a user defined absolute value for the penalty stiffness (pf ac < 0). With this option activated the code automatically accounts for the contact stiffness and reduces the time step if necessary in order to maintain numerical stability. If mass scaling is activated (see ∆tmin in TIME) mass is added where needed to compensate for the contact stiffness. Time histories of contact forces, energies, artificially added contact interface mass and maximum contact penetration are output to the ASCII file contact.out The time history data can be visualized with IMPETUS Afea Post Processor. Rigid shell elements must be oriented such that the element face normals (right hand rule) point towards the object they are to be in contact with. IMPETUS Afea Solver v.3.0 142 Contact and ed interfaces *MERGE *MERGE entypes , enids , entypem , enidm , tol, mfid, gid Parameter defini on Variable Description entypes Slave entity type options: P, PS Slave entity identification number Master entity type options: P, PS Master entity identification number Tolerance for merging default: 1% of the master face side length ID of MERGE FAILURE command default: no failure ID of GEOMETRY defining the region to be merged default: no geometry enids entypem enidm tol mfid gid Descrip on This command can be used to merge disjointed meshes. IMPETUS Afea Solver v.3.0 143 Contact and ed interfaces *MERGE FAILURE COHESIVE *MERGE FAILURE COHESIVE mfid, σf ail , τf ail , GI , GII , ∆ref Parameter defini on Variable Description mfid σf ail τf ail GI GII ∆ref Merge failure command ID Tensile failure stress Shear failure stress Modus I energy per unit area Modus II energy per unit area Element reference size Descrip on Specifies failure of a merged interface MERGE. Failure is initiated when: ( ξσ σf ail )2 ( + ξτ τf ail )2 ≥1 where ξ is a scale factor accounting the inability to resolve stress concentrations at coarse element grids: √ ξ = max(1, ∆/∆ref ) ∆ is the local characteristic element size on the slave side of the merge interface. The stress unloading from failure is a linear function of the crack opening distance. It is defined such that the consumed energy per unit area of cracking G is: √( )2 ( )2 σ τ GI + GII G= σf ail τf ail IMPETUS Afea Solver v.3.0 144 Contact and ed interfaces *MERGE FAILURE FORCE *MERGE FAILURE FORCE mfid, Tf ail , Sf ail Parameter defini on Variable Description mfid Tf ail Sf ail Merge failure command ID Tensile failure force Shear failure force Descrip on Specifies failure of a merged interface MERGE. Failure is initiated when: ( T Tf ail )2 ( + S Sf ail )2 ≥1 where T and S is the total tensile force and shear force between the merged interfaces, respectively. Note that compressive forces will not lead to failure. IMPETUS Afea Solver v.3.0 145 Rigid bodies Rigid bodies *RIGID *RIGID *RIGID *RIGID BODY BODY BODY BODY IMPETUS Afea Solver v.3.0 DAMPING INERTIA JOINT MERGE 146 Rigid bodies *RIGID BODY DAMPING *RIGID BODY DAMPING pid1 , pid2 , C, tbeg , tend Parameter defini on Variable Description pid1 pid2 C tbeg tend Rigid body part ID 1 Rigid body part ID 2 Damping coefficient Start time End time Descrip on Applies a damping force between two rigid bodies. The force is defined as: F = C · (vpid1 − vpid2 ) IMPETUS Afea Solver v.3.0 147 Rigid bodies *RIGID BODY INERTIA *RIGID BODY INERTIA pid, m, xc , yc , zc , I11 , I22 , I33 I12 , I23 , I31 Parameter defini on Variable Description pid m xc , yc , zc I11 , I22 , I33 I12 , I23 , I31 Rigid body part ID Rigid body mass Center of gravity Moment of inertia (diagonal terms) Moment of inertia (off-diagonal terms) Descrip on This command allows the user to define the mass, center of gravity and moment of intertia of a rigid body. IMPETUS Afea Solver v.3.0 148 Rigid bodies *RIGID BODY JOINT *RIGID BODY JOINT coid entype1 , enid1 , entype2 , enid2 , bctr , bcrot , csysid1 , csysid2 rx−, rx+, ry−, ry+, rz−, rz+, gap cidx , cidy , cidz Parameter defini on Variable Description coid entype1 Joint ID Entity type 1 options: P, CR Entity identification number 1 Entity type 2 options: P, CR Entity identification number 2 Constrained translational degrees of freedom options: X, Y, Z, XY, YZ, ZX, XYZ Constrained rotational degrees of freedom options: X, Y, Z, XY, YZ, ZX, XYZ ID of coordinate system defining initial location of joint and orientation of Entity 1 default: global coordinates are used ID of coordinate system defining initial orientation of Entity 2 default: csysid2 = csysid1 Maximum free rotation angle around x-axis in negative direction (deg) Maximum free rotation angle around x-axis in positive direction Maximum free rotation angle around y-axis in negative direction Maximum free rotation angle around y-axis in positive direction Maximum free rotation angle around z-axis in negative direction Maximum free rotation angle around z-axis in positive direction Joint gap in all directions (clearance) default: no gap ID of CURVE describing rotational resistance (torque) as function of rotation angle around x-axis (deg) default: no rotational resistance ID of CURVE describing rotational resistance (torque) as function of rotation angle around y-axis default: no rotational resistance ID of CURVE curve describing rotational resistance (torque) as function of rotation angle around z-axis default: no rotational resistance enid1 entype2 enid2 bctr bcrot csysid1 csysid2 rx− rx+ ry− ry+ rz− rz+ gap cidx cidy cidz Descrip on This command defines a joint between two rigid bodies or rigid connectors (see CONNECTOR RIGID). The joint is initially centered at the origin of csysid1 . csysid1 also defines initial local directions in which the joint constraints are defined and forces/torques are output. csysid2 is used to define non-zero relative rotations at the IMPETUS Afea Solver v.3.0 149 Rigid bodies initial state. csysid2 is only needed if the free rotations are limited or if rotational resistance is defined. The joint rotation angle is defined as the rotation of enid2 minus the rotation of enid1 . A non-zero initial rotation angle can be defined though csysid1 and csysid2 . IMPETUS Afea Solver v.3.0 150 Rigid bodies *RIGID BODY MERGE *RIGID BODY MERGE setid Parameter defini on Variable Description setid Rigid body part set ID Descrip on This command is used to merge rigid bodies. The part with the lowest ID becomes the master. The master part ID or title is the one being referred to in the ASCII output file rigid.out. IMPETUS Afea Solver v.3.0 151 Connectors Connectors *CONNECTOR RIGID *CONNECTOR SPR *CONNECTOR SPRING IMPETUS Afea Solver v.3.0 152 Connectors *CONNECTOR RIGID *CONNECTOR RIGID coid, entype, enid Parameter defini on Variable Description coid entype Connector ID Entity type options: NS, G Entity ID enid Descrip on This command adds rigid connections between a set of nodes, so that the set of nodes will behave like a rigid body. The motion of and the forces acting on the connectors is output to the ASCII file connector rigid.out. IMPETUS Afea Solver v.3.0 153 Connectors *CONNECTOR SPR *CONNECTOR SPR coid, pids , pidm , csysid R, h, m, fnmax , ftmax , dmax , dmax , ξn n t ξt , a1 , a2 , a3 Parameter defini on Variable Description coid pids pidm csysid R h m fnmax ftmax dmax n dmax t ξn ξt a1 , a2 , a3 SPR connector ID Slave part ID Master part ID Coordinate system ID defining location of rivet Rivet radius Rivet height Rivet mass Pull-out strength Shear strength Pull out failure displacement Shear failure displacement Dimensionless parameter controlling the shape of the force pull-out curve Dimensionless parameter controlling the shape of the force shear displacement curve Parameters defining the strength in directions between pure pull-out and pure shear Descrip on This is a point connector model that couples a group of nodes on a slave sheet with a group of nodes on a master sheet. The members in the groups are those nodes located inside the rivet, defined through location, radius and height. At least three nodes on each side are required for a consistent transfer of forces and moments. The rivet radius is automatically increased in case not enough nodes are located within the specified rivet geometry. Hanssen et al. (2010) provides a detailed description of the model. A brief description follows below. The rivet normal and shear forces are: fn = dn fˆn (η max ) max η dmax n ft = dt fˆt (η max ) max η dmax t where dn and dt are the rivet elongations in the normal and tangential directions. η max is a damage measure that grows from 0 to 1. { η˙ : η = η max max η˙ = 0 : η < η max IMPETUS Afea Solver v.3.0 154 Connectors fˆn (η max ) and fˆt (η max ) are force-displacement curves (see figure below). Figure 26: η is a normalized effective displacement: η = [ξ + (1 − ξ)a] √ (dn /dmax )2 + (dt /dmax )2 n t ξ is a parameter ranging from 0 to 1 and it scales the effective displacement as a function of the direction of the displacement vector in the (dt , dn )-plane. 27 ξ =1− 4 ( 2θ π )2 27 + 4 ( 2θ π )3 where θ = arctan(dn /dt ). The directional scaling is allowed to change as damage evolves. This is done by defining the following relationship for the shape coefficient a: { max ξt −η max a1 + η ξt a2 : η max < ξt ξt max a= 1−η max a2 + η ξt−ξt a3 : η max ≥ ξ ξt IMPETUS Afea Solver v.3.0 155 Connectors *CONNECTOR SPRING *CONNECTOR SPRING coid, N1 , N2 , m, k, ξ, Ff ail , direc Parameter defini on Variable Description coid N1 N2 m k Spring connector ID Node 1 Node 2 Mass Stiffness (force per unit distance of elongation) or a FUNCTION defining the elastic force versus elongation Fraction of critical damping or a FUNCTION defining the damping force versus elongation rate Spring failure force default: No failure Spring force direction options: 0 → tension and compression 1 → tension only 2 → compression only ξ Ff ail direc Descrip on This command defines a linear spring between two nodes. IMPETUS Afea Solver v.3.0 156 Parameters and func ons Parameters and func ons *CURVE *FUNCTION *FUNCTION STATIC *PARAMETER IMPETUS Afea Solver v.3.0 157 Parameters and func ons *CURVE *CURVE cid, sfx , sfy x 1 , y1 . x n , yn Parameter defini on Variable Description cid sfx Curve identification number Scale factor for abscissa values default: 1 Scale factor for ordinate values default: 1 First abscissa ordinate pair Last abscissa ordinate pair sfy x 1 , y1 x n , yn Descrip on Definition of a piecewise linear curve. Note that a curve and a function (see FUNCTION) can not have the same ID. IMPETUS Afea Solver v.3.0 158 Parameters and func ons *FUNCTION *FUNCTION fid, derivative, f (0), f˙(0) expression Parameter defini on Variable Description fid derivative Function ID Function derivative level options: 0 → f (., t) = expression 1 → f˙(t) = expression 2 → f¨(t) = expression Function value at time 0 (used if derivative > 0) First derivative of function at time 0 (used if derivative = 2) Analytical expression f (0) f˙(0) expression Descrip on This command can be used to define analytical functions to be used in the same way as curves (see CURVE) when applying loads or boundary conditions. Note that a curve and a function can not have the same ID. Functions can be defined to depend on certain simulation results, for example node velocities and contact forces. A complete listing of built in functions and parameters is given in the General section. If derivative=1 the expression defines the first derivative of the function (with respect to time): ∫ t f (t) = f (0) + (expression)dτ 0 With derivative=2 the expression defines the second derivative of the function: ] ∫ t[ ∫ τ 0 ˙ f (t) = f (0) + f (0) + (expression)dτ dτ 0 IMPETUS Afea Solver v.3.0 0 159 Parameters and func ons *FUNCTION STATIC *FUNCTION STATIC fid expression Parameter defini on Variable Description fid expression Function ID Analytical expression Descrip on This command is used to define a field at time zero. The function is evaluated at each node or integration point during initialization. The values are accessible throughout out the simulation and are typically used to define properties of functionally graded materials. IMPETUS Afea Solver v.3.0 160 Parameters and func ons *PARAMETER *PARAMETER %param = expression, description Parameter defini on Variable Description %param = expression description Parameter name and an expression defining its value Optional parameter description Descrip on The purpose of this command is to define parameters, that can be used inside expressions anywhere in the command file. Brackets are used to mark the beginning and end of an expression. Parameters should always be preceeded by the prefix %. IMPETUS Afea Solver v.3.0 161 Geometries Geometries *GEOMETRY *GEOMETRY *GEOMETRY *GEOMETRY *GEOMETRY *GEOMETRY *GEOMETRY IMPETUS Afea Solver v.3.0 BOX EFP PART PIPE SEED COORDINATE SEED NODE SPHERE 162 Geometries *GEOMETRY BOX *GEOMETRY BOX gid, csysid x 1 , y1 , z 1 , x 2 , y2 , z 2 Parameter defini on Variable Description gid csysid Geometry identification number Local coordinate system ID default: global coordinate system is used Box corner coordinate 1 Box corner coordinate 2 x1 , y1 , z1 x2 , y2 , z2 Descrip on This command is used to define a box in space, with corner coordinates at (x1 , y1 , z1 ) and (x2 , y2 , z2 ). Figure 27: box IMPETUS Afea Solver v.3.0 163 Geometries *GEOMETRY EFP *GEOMETRY EFP gid, csysid x1 , y1 , z1 , x2 , y2 , z2 , R1 , R2 Parameter defini on Variable Description gid csysid Geometry identification number Local coordinate system ID default: global coordinate system is used Face center coordinate 1 Face center coordinate 2 Cylinder radius Top face radius x1 , y1 , z1 x2 , y2 , z2 R1 R2 Descrip on This command is used to define the shape of a charge for an explosively formed projectile (EFP) with face center coordinates at (x1 , y1 , z1 ) and (x2 , y2 , z2 ), radius R1 and top face radius R2 . Figure 28: efp IMPETUS Afea Solver v.3.0 164 Geometries *GEOMETRY PART *GEOMETRY PART gid pid Parameter defini on Variable Description gid pid Geometry identification number Part ID Descrip on This command is used to define a geometry with the shape of a part. IMPETUS Afea Solver v.3.0 165 Geometries *GEOMETRY PIPE *GEOMETRY PIPE gid, csysid x1 , y1 , z1 , x2 , y2 , z2 , R1 , R2 Parameter defini on Variable Description gid csysid Geometry identification number Local coordinate system ID default: global coordinate system is used Face center coordinate 1 Face center coordinate 2 First radius at face 1 Second radius at face 2 x1 , y1 , z1 x2 , y2 , z2 R1 R2 Descrip on This command is used to define a straight pipe or cylinder in space, with its face center coordinates at (x1 , y1 , z1 ) and (x2 , y2 , z2 ). Note that the smaller of R1 and R2 is automatically taken as the inner radius. Figure 29: pipe IMPETUS Afea Solver v.3.0 166 Geometries *GEOMETRY SEED COORDINATE *GEOMETRY SEED COORDINATE gid x, y, z, αc Parameter defini on Variable Description gid x y z αc Geometry identification number x-coordinate y-coordinate z-coordinate Cut-off angle default: 45◦ Descrip on This command is used to define a surface from a seed coordinate. The surface propagates from the external element face nearest the given seed coordinate. αc is the angle between two faces that defines the boundary of the surface (default αc = 45◦ ). IMPETUS Afea Solver v.3.0 167 Geometries *GEOMETRY SEED NODE *GEOMETRY SEED NODE gid nid1 , nid2 , αc Parameter defini on Variable Description gid nid1 , nid2 αc Geometry identification number Seed nodes Cut-off angle default: 45◦ Descrip on This command is used to define a surface from seed nodes with ID nid1 and nid2 . nid2 only needs to be given if nid1 is located on an edge (see figure below). αc is the angle between two faces that defines the boundary of the surface (default αc = 45◦ ). Figure 30: seed node IMPETUS Afea Solver v.3.0 168 Geometries *GEOMETRY SPHERE *GEOMETRY SPHERE gid, csysid x, y, z, R Parameter defini on Variable Description gid csysid Geometry identification number Local coordinate system ID default: global coordinate system is used Sphere center coordinate Sphere radius x, y, z R Descrip on This command is used to define a sphere in space, with its center at (x, y, z) and with radius R. Figure 31: sphere IMPETUS Afea Solver v.3.0 169 Sets Sets *SET *SET *SET *SET *SET ELEMENT FACE GEOMETRY NODE PART IMPETUS Afea Solver v.3.0 170 Sets *SET ELEMENT *SET ELEMENT setid eid1 , ..., eid8 . eidM , ..., eidN Parameter defini on Variable Description setid eid1 , ..., eid8 eidM , ..., eidN Unique element set identification number Element identification number 1 to 8 Element identification number M to N Descrip on This command defines a set of elements. IMPETUS Afea Solver v.3.0 171 Sets *SET FACE *SET FACE setid nid11 , nid12 , nid13 , nid14 . nidN1 , nidN2 , nidN3 , nidN4 Parameter defini on Variable Description setid nid11 , nid12 nid13 , nid14 nidN1 , nidN2 nidN3 , nidN4 Unique face set identification number Corner node ids of the first face in the list Corner node ids of the last face in the list Descrip on This command defines a set of faces. IMPETUS Afea Solver v.3.0 172 Sets *SET GEOMETRY *SET GEOMETRY setid gid1 , ..., gid8 . gidM , ..., gidN Parameter defini on Variable Description setid gid1 , ..., gid8 gidM , ..., gidN Unique geometry set identification number Geometry identification number 1 to 8 Geometry identification number M to N Descrip on This command defines a set of geometries (see e.g. GEOMETRY BOX). IMPETUS Afea Solver v.3.0 173 Sets *SET NODE *SET NODE setid nid1 , ..., nid8 . nidM , ..., nidN Parameter defini on Variable Description setid nid1 , ..., nid8 nidM , ..., nidN Unique node set identification number Node identification number 1 to 8 Node identification number M to N Descrip on This command defines a set of nodes. IMPETUS Afea Solver v.3.0 174 Sets *SET PART *SET PART setid range1 , ..., rangeK . rangeM , ..., rangeN Parameter defini on Variable Description setid range1 , ..., rangeK rangeM , ..., rangeN Unique part set identification number Part ID range 1 to K Part ID range M to N Descrip on This command defines a set of parts. A range is either a part ID (e.g. 10), or a range of parts (e.g. 10..20). IMPETUS Afea Solver v.3.0 175 Coordinate system Coordinate system *COORDINATE SYSTEM CYLINDRICAL *COORDINATE SYSTEM FIXED *COORDINATE SYSTEM NODE IMPETUS Afea Solver v.3.0 176 Coordinate system *COORDINATE SYSTEM CYLINDRICAL *COORDINATE SYSTEM CYLINDRICAL csysid, x0 , y0 , z0 ˆ 0x , R ˆ 0y , R ˆ 0z zˆx , zˆy , zˆz , R Parameter defini on Variable Description csysid x0 y0 z0 zˆx zˆy zˆz ˆ 0x R ˆ 0y R ˆ 0z R Unique identification number X-coordinate of a point on the cylinder axis Y-coordinate of a point on the cylinder axis Z-coordinate of a point on the cylinder axis X-component of axial direction Y-component of axial direction Z-component of axial direction X-component of radial direction at θ = 0 Y-component of radial direction at θ = 0 Z-component of radial direction at θ = 0 Descrip on Defines a fixed local cylindrical coordinate system. A point on the cylindrical center axis is located at (x0 , y0 , x0 ) and the local axial direction is (ˆ zx , zˆy , zˆz ). Figure 32: Cylindrical coordinate system IMPETUS Afea Solver v.3.0 177 Coordinate system *COORDINATE SYSTEM FIXED *COORDINATE SYSTEM FIXED csysid, x0 , y0 , z0 x ˆx , x ˆy , x ˆz , y¯x , y¯y , y¯z Parameter defini on Variable Description csysid x0 , y0 , z0 x ˆx , x ˆy , x ˆz y¯x , y¯y , y¯z Unique identification number Coordinate of origin Direction of local x-axis Vector needed for the definition of the local y- and z-axis Descrip on Defines a fixed local cartesian coordinate system. The system is defined through the input of direction cosines. The origin is located at (x0 , y0 , z0 ) and the local x-direction is (ˆ xx , x ˆy , x ˆz ). The local z-direction is defined as ˆz = ˆx × ¯y/|ˆx × ¯y| and the local y-direction as ˆy = ˆz × ˆx. IMPETUS Afea Solver v.3.0 178 Coordinate system *COORDINATE SYSTEM NODE *COORDINATE SYSTEM NODE csysid, N1 , N2 , N3 Parameter defini on Variable Description csysid N1 , N 2 , N 3 Unique identification number Nodes defining the location and direction of the local system Descrip on Defines a local cartesian coordinate system. The system is defined through 3 user defined nodes. This system will automatically be updated if the nodes are moving. The local x-direction, ˆx, is defined as the direction of a vector pointing from node N1 to N2 . The local z-direction, ˆz is defined as the cross product of ˆx and the vector pointing from N1 to N3 . The local y-direction is ˆy = ˆz × ˆx. Figure 33: Coordinate system defined by three nodes IMPETUS Afea Solver v.3.0 179 Discrete Par cles Discrete Par cles *PBLAST *PBLAST AIR *PSOIL IMPETUS Afea Solver v.3.0 180 Discrete Par cles *PBLAST *PBLAST entype, enid, air, soil, he, Np bcx0 , bcx1 , bcy0 , bcy1 , bcz0 , bcz1 , µ gidglob , gidsoil , gidhe , x0 , y0 , z0 , t0 , tend pack, ρs , ks , µs , ξs ρhe , ehe , γhe , vhe , Dhe Parameter defini on Variable Description entype Structure entity type for particle structure interaction options: P, PS, ALL Structure entity ID Air activation flag options: 0 → air is not included 1 → air is included Soil type options: 0 (no soil), dry, wet, user High explosive type options: 0 (no HE), tnt, c4, petn, m46, user Total number of particles Boundary conditions for global domain xmin options: 0 → free 1 → rigid reflecting boundary Boundary condition for global domain xmax Boundary condition for global domain ymin Boundary condition for global domain ymax Boundary condition for global domain zmin Boundary condition for global domain zmax Soil-structure contact coefficient of friction ID of a GEOMETRY defining the global domain ID of a GEOMETRY defining the soil domain ID of a GEOMETRY defining the high explosives domain Detonation point Detonation time Particle deactivation end time Soil packing scheme (this line is only used if soil=user) options: 1 → dry soil (unit cell with 1k particles) 2 → wet soil (1k) 3 → dry soil (10k) 4 → wet soil (10k) Soil density Soil-soil contact stiffness enid air soil he Np bcx0 bcx1 bcy0 bcy1 bcz0 bcz1 µ gidglob gidsoil gidhe x0 , y0 , z0 t0 tend pack ρs ks IMPETUS Afea Solver v.3.0 181 Discrete Par cles µs ξs ρhe ehe γhe vhe Dhe Soil-soil contact coefficient of friction Soil-soil damping coefficient HE density (this line is only used if type he=user) HE energy per unit volume HE fraction between Cp and Cv HE co-volume at density=ρHE HE detonation velocity Descrip on This command defines the blast loading of an FE-structure with air, soil and high explosive. Note that this command requires a unit system to be specified (see UNIT SYSTEM). Borvik et al. (2011) provides a comprehensive description of the discrete particle method and of the used input parameters. Note that reflective boundary conditions will be applied to global domain boundaries that coincide with a BC SYMMETRY definition. IMPETUS Afea Solver v.3.0 182 Discrete Par cles *PSOIL *PSOIL entype, enid, gidglob , gidsoil , soil, Np , µ, tend bcx0 , bcx1 , bcy0 , bcy1 , bcz0 , bcz1 , pack, ρs , ks , µs , ξs Parameter defini on Variable Description entype Structure entity type for particle structure interaction options: P, PS, ALL Structure entity ID ID of a GEOMETRY defining the global domain ID of a GEOMETRY defining the soil domain Soil type options: dry, wet, user Total number of particles Soil-structure contact coefficient of friction Particle deactivation end time Boundary conditions for global domain xmin options: 0 → free 1 → rigid reflecting boundary Boundary condition for global domain xmax Boundary condition for global domain ymin Boundary condition for global domain ymax Boundary condition for global domain zmin Boundary condition for global domain zmax Soil packing scheme (this line is only used if soil=user) options: 1 → dry soil (unit cell with 1k particles) 2 → wet soil (1k) 3 → dry soil (10k) 4 → wet soil (10k) Soil density Soil-soil contact stiffness Soil-soil contact coefficient of friction Soil-soil damping coefficient enid gidglob gidsoil soil Np µ tend bcx0 bcx1 bcy0 bcy1 bcz0 bcz1 pack ρs ks µs ξs Descrip on This command defines a domain filled with discrete particles representing sand or soil. Note that reflective boundary conditions will be applied to global domain boundaries that coincide with a BC SYMMETRY definition. IMPETUS Afea Solver v.3.0 183 Smoothed Par cle Hydrodynamics Smoothed Par cle Hydrodynamics *SPH FLUID *SPH SENSOR PRESSURE *SPH WATER ENTRY LAB IMPETUS Afea Solver v.3.0 184 Smoothed Par cle Hydrodynamics *SPH FLUID *SPH FLUID entype, enid, form, vmax , giddel , ∆tc pid1 , gid1 , dx1 , dy1 , dz1 , α1 , β1 . pidn , gidn , dxn , dyn , dzn , αn , βn Parameter defini on Variable Description entype Structure entity type for SPH-structure interaction options: P, PS Structure entity ID Formulation type options: 1 → fluid (default) 2 → gas and fluid 3 → Godunov (no artificial viscosity) 4 → renormalized 101 → symplectic fluid Maximum SPH node velocity Geometry defining a bounding box for SPH node deletion SPH contact time step size Part ID Geometry ID that defines a region is space that will be filled with SPH nodes Node spacing in x-direction Node spacing in y-direction default: dy1 = dx1 Node spacing in z-direction default: dz1 = dx1 Linear artificial viscosity term default: 0.1 Quadratic artificial viscosity term default: 0.5 Part ID Geometry ID that defines a region is space that will be filled with SPH nodes Node spacing in x-direction Node spacing in y-direction default: dyn = dxn Node spacing in z-direction default: dzn = dxn Linear artificial viscosity term default: 0.1 Quadratic artificial viscosity term default: 0.5 enid form vmax giddel ∆tc pid1 gid1 dx1 dy1 dz1 α1 β1 pidn gidn dxn dyn dzn αn βn IMPETUS Afea Solver v.3.0 185 Smoothed Par cle Hydrodynamics Descrip on Defines SPH fluid geometries/grids and interaction between SPH nodes and structure. IMPETUS Afea Solver v.3.0 186 Smoothed Par cle Hydrodynamics *SPH SENSOR PRESSURE *SPH SENSOR PRESSURE sid, gid Parameter defini on Variable Description sid gid Sensor ID Geometry defining the location of the sensor Descrip on Defines a sensor for pressure sampling. The pressure is output to the ASCII file sph sensor pressure.out. The pressure is calculated as the average pressure of all SPH particles inside the geometry with ID gid. IMPETUS Afea Solver v.3.0 187 Smoothed Par cle Hydrodynamics *SPH WATER ENTRY LAB *SPH WATER ENTRY LAB entype, enid, L, W , D, Np , vmax bcx0 , bcx1 , bcy0 , bcy1 , bcz0 Parameter defini on Variable Description entype Structure entity type for SPH-structure interaction options: P, PS Structure entity ID Length of water domain (x-direction) Width of water domain (y-direction) default: 0 (2D formulation) Depth of water domain (z-direction) Number of SPH particles Maximum expected water velocity Boundary conditions for water domain xmin options: 0 → reflective 1 → absorbing 2 → free Boundary condition for water domain xmax Boundary condition for water domain ymin Boundary condition for water domain ymax Boundary condition for water domain zmin enid L W D Np vmax bcx0 bcx1 bcy0 bcy1 bcz0 Descrip on Defines a basin of water modeled with SPH. The command currently only supports SI-units. The command UNIT SYSTEM needs to be defined. The neutral water level is always at z = 0. IMPETUS Afea Solver v.3.0 188 text | CONTACT NORWAY: IMPETUS Afea AS Strandgaten 32, N-4400 Flekkefjord, Norway Phone: + 47 38 37 66 70 CONTACT SWEDEN: IMPETUS Afea AB Sordalavagen 22, SE-14169 Huddinge, Sweden Phone: + 46 8 774 57 10 [email protected] http://www.impetus-afea.com CONTACT FRANCE: IMPETUS Afea SAS 6 rue du Cers, FR-31330 Grenade sur Garonne, France Phone: +33 561 74 86 82
© Copyright 2024