Advances in Nuclear Fuel Management V

Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Hilton Head Island, SC
Official Program
http://anfm2015.org
ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Foreword
Welcome to the American Nuclear Society’s Advances in Nuclear Fuel Management topical meeting. The 2015 edition of
this meeting is the fifth in the series, held every six years. It has become a tradition to hold the meeting in early spring in
sunny Hilton Head, South Carolina. We hope you enjoy everything the area has to offer. Please let any member of the
organizing committee know if you have any questions or concerns. Volunteers from the Columbia, SC Local Section will be
wearing navy blue polo shirts, and they will be happy to help you with information about the local area.
Thank you for attending and supporting the important work of the American Nuclear Society and all our co-sponsoring international organizations.
Bill Herwig, General Chairman
Damon Bryson, Assistant General Chair
Acknowledgement
The organizing committee would like to thank the following:
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Our financial sponsors for their generous contributions to the success of the meeting. Please take the time to thank
them for their commitment.
Our co-sponsoring technical societies and ANS technical divisions for helping us to publicize the meeting.
The technical program committee for soliciting papers, organizing and performing paper reviews, and chairing our
technical sessions.
Ms. Hanna Shapira (TICS) for management of the website, registration, program booklet, and CD.
Our panel and plenary session speakers, who were willing to accept another assignment on top of an already
hectic schedule.
RSICC - Radiation Safety Information Computational Center (ORNL) for the duplication of the CDs.
The Consortium for Advanced Simulation of LWRs (CASL) for co-locating their workshop at the end of the conference.
Finally, I would personally like to thank the organizing committee, who have done an outstanding job of coordinating the program and the meeting arrangements. What we lacked in face-to-face meetings we made up for in
e-mails, faxes, conference calls, and every other form of communication possible to get the meeting planned. The
hours you spent ensuring a successful meeting are very much appreciated; the meeting simply wouldn’t have happened without your dedication.
Bill Herwig, General Chairman
Damon Bryson, Assistant General Chair
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ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Organizing Committee
General Chair
Assistant General Chair
Past Chair & Advisor
Technical Program
Co-chair
Co-chair
Co-chair
Publications Finance Registration/Web Apps Publicity Sponsors/Fundraising Tours/Events Banquet Coordinator Workshops Student Volunteer Coordinator
Bill Herwig, SCE&G
Damon Bryson, SCE&G
John Siphers, Progress Energy
Ivan Maldonado, University of Tennessee
Atul Karve, Global Nuclear Fuel
Ron Ellis, ORNL
Elise Malek, Westinghouse
Duane Twining, SCE&G
Hanna Shapira, TICSs Lisa Marshall, NC State University
Sarah Gillham, Southern Nuclear
Caroline Duncan, Westinghouse
Courtney Tampas, SCE&G
Rose Montgomery, TVA
Matthew Presson, SCE&G
Jamel Bell, SCE&G
Bill Herwig
Damon Bryson
John Siphers
Ivan Maldonado
Atul Karve
Ron Ellis
Elise Malek Duane Twining
Hanna Shapira
Lisa Marshall
Sarah Gillham
Caroline Duncan
Courtney Tampas
Rose Montgomery
Matthew Presson
Jamel Bell
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ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Technical Program Committee
Tunc Aldemir, OSU, USA
Mehdi Asgari, Studsvik Scandpower, USA
Brian Aviles, KAPL, USA
Paul Bailey, Duke, USA
Steve Baker, Transware, USA
Jeff Borkowski, Studsvik Scandpower, USA
Robb Borland, First Energy, USA
Steve Bowman, ORNL, USA
Jeff Bradfute, Westinghouse, USA
Juan Casal, Westinghouse, Sweden
Angelo Chopelas, GNF, USA
Dimitrios Cokinos, BNL, USA
Chris Comfort, Southern, USA
Edmundo Del Valle Gallegos, IPN, Mexico
Arthur DiGiovine, Studsvik Scandpower, USA
Alex Dolgov, TVEL, Russia
Tom Downar, Univerity of Michigan, USA
Mike Dunn, ORNL, USA
Troy Eckleberry, TVA, USA
Bob Einziger, NRC/US, USA
Ronald Ellis, ORNL, USA
Filip Fejt, Technical Univ at Prague, Czech Rep
Fausto Franceschini, Westinghouse, USA
Juan Luis Francois, UNAM, Mexico
Norman Garner, AREVA, USA
Kenneth Geelhood, PNNL, USA
Jess Gehin, ORNL, USA
Ali Haghighat, UFL, USA
Ayman Hawari, NCSU, USA
Charles Heck, GNF, USA
William Herwig, SCANA, USA
Jim Hoerner, AREVA, USA
Nadine Hollasky, Bel V, Belgium
Clive Ingram, Office of Nuclear Regulation, United Kingdom
Victor Inozemtsev, IAEA, Int.
Kostadin Ivanov, PSU, USA
John Jones, Office of Nuclear Regulation, United Kingdom
Atul Karve, GNF, USA
Doddy Kastanya, Candu Energy, Canada
Paul Keller, Areva, USA
Hany Khalik, Purdue University, USA
Travis Knight, USC, USA
Dave Knott, Studsvik Scandpower, USA
Tomasz Kozlowski, University of Illinois, USA
Dave Kropaczek, Studsvik Scandpower, USA
Vefa Kucukboyaci, Westinghouse,
Maria Teresa Lopez Carbonell, IBERDROLA, Spain
Ivan Maldonado, University of Tennessee, USA
Christian Malm, Vattenfall, Sweden
Cecilia Martin-del-Campo, UNAM, Mexico
K Matsuura, NFI, Japan
Vaclav Mecir, CEZ, CZECH
Ugur Mertyurek, ORNL, USA
Mitch Meyer, INL, USA
Pierre Mollard, AREVA, France
Rob Montgomery, PNNL, USA
Rose Montgomery, TVA, USA
Brian Moore, GNF, USA
Bruce Morgen, Duke, USA
Rahim Nabbi, Juelich Research Center, Germany
Eleodor (Dorin) Nichita, UOIT/AECL, Canada
Chvala Ondrej, University of Tennessee, USA
Shinji Ono, Westinghouse/NFI, Japan
Abderrafi Ougouag, INEL, USA
Mohamed Ouisloumen, Westinghouse, USA
Scott Palmtag, Core Physics, USA
Bojan Petrovic, GA Tech, USA
Dubravko Pevec, University of Zagreb, Croatia
Trent Primm, Primm Consulting, USA
Zhao Qiang, Harbin Eng University, China
Manuel Quecedo, ENUSA, Spain
Farzad Rahnema, GA Tech, USA
Sumit Ray, Westinghouse, USA
Tony Reese, GNF, USA
Michael Reitmeyer, Exelon, USA
Javier Riverola, ENUSA, Spain
Kan Sakamoto, NFD, Japan
Alain Santamaria, CEA, France
Hitoshi Sato, GNF, Japan
Jeff Secker, Westinghouse, USA
Koroush Shirvan, MIT, USA
John Siphers, Duke, USA
Steve Skutnik, University of Tennessee, USA
Russell Stachowski, GNF, USA
Bob StClair, Duke Energy, USA
Marco Streit, Paul Scherrer Institut, Switzerland
John Strumpell, AREVA, USA
Scott Thomas, Duke Energy, USA
Jim Tulenko, UFL/US, USA
Paul Turinsky, NCSU, USA
Michael Tusar, Exelon, USA
Tadashi Ushio, NFI, Japan
Mojmir Valach, NRI, Czech Republic
Nicolas Waeckel, EDF, France
Fu Xiangang, CGNPC, China
Peng Xu, Westinghouse, USA
Akio Yamamoto, Nagoya University, Japan
Masatoshi Yamasaki, NFI, Japan
Koo Yang-Hyun, KAERI, Korea
Ying Yi, SNERDI, China
Serkan Yilmaz, GNF, USA
Hiroyuki Yoshida, Toshiba, Japan
Quun Zee, KAERI, South Korea
Hongbin Zhang, INL, USA
Jinzhao Zhang, Tractebel Eng / GDF SUEZ, Belgium
A special thank you and recognition for the following individuals for being engaged, flexible, and for volunteering the time in
completing the many comprehensive reviews the Technical Program Co-chairs solicited of them. Their constructive feedback review
ensured that the papers continue to be of exceptional quality and live up to the high standards for this conference.
Christian Malm, Vattenfall
Norman Garner, Areva
Jim Hoerner, Areva
Vefa Kucukboyaci, Westinghouse
John Jones, Office of Nuclear Regulation, UK
Doddy Kastanya, Candu Energy, Canada
Tomasz Kozlowski, University of
Illinois, USA
Russell Stachowski, GNF, USA
Koroush Shirvan, MIT, USA
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Dimitrios Cokinos, BNL, USA
Masatoshi Yamasaki, NFI, Japan
Jeff Secker, Westinghouse, USA
Akio Yamamoto, Nagoya University, Japan
Nadine Hollasky, Bel V, Belgium
Advances in Nuclear Fuel Management V
29 - April 1, 2015
ANFM 2015 - Advances in Nuclear Fuel Management V
March
March 29 - April 1, 2015
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• ANS - Columbia SC Section
• ANS - Reactor Physics Division
• ANS - Fuel Cycle and Waste Management Division
• ENS - European Nuclear Society
• CNS - Canadian Nuclear Society
• AESJ - Atomic Energy Society of Japan
• KNS - Korean Nuclear Society
• SNM - Mexican Nuclear Society
• OECD/NEA - Organizatin for Economic Cooperation & Development/Nuclear Energy Agency
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ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
General Information
Registration
Session Chair Information
Registration is required for all attendees and presenters.
Badges are required for admission to all events.
Please complete and return a “Session Chair Sign-in Form.”
Please attend the Breakfast (7-8am) on the day of your session and be present at your session room at least 15 minutes
prior to the start of the session. This will allow you to greet
and coordinate media arrangements with the speakers, as
well as collect biographical sketches. For the sake of meeting
attendees, PLEASE keep the session perfectly synchronized
as shown in this final program. For “no shows” simply adjourn
the session at the next allotted time (i.e., don’t shift papers to
earlier slots to fill a void). You may find it helpful to bring your
own laptop and upload the speakers’ presentations during
the breakfast or pre-session meetings. Alternatively, please
ensure there is a laptop available for facilitating presentations
during your entire session. You will have a student assistant to
assist you during the meeting. You may use his/her assistance
to drive the presentation, help with A/V etc. He/She will checkin with you prior to the start of the session and ask you to sign
a confirmation of assistance at the end of the session.
The Full Conference Registration Fee for Member
and Non-Member includes: All technical sessions, CD of all
proceedings, coffee breaks/snacks, and Sunday night reception. Registration does not include Monday night dinner or
Tuesday night banquet.
The One Day Conference fee for Member and NonMember includes: All technical sessions for the registration
day, coffee breaks/snacks, and CD of proceedings. Does not
include dinner ticket.
The Student Registration Fee includes: All technical
sessions, CD of all proceedings, coffee breaks/snacks, and
Sunday night reception. Registration does not include Monday
night dinner or Tuesday night banquet.
Spouse/Guest includes: Sunday night reception, but does
not include Monday night dinner or Tuesday night banquet.
The Meeting Registration Desk is at Palmetto Landing:
Sunday
Monday-Wednesday 3:00 PM – 5:00 PM
7:15 AM – 8:00 AM
Speaker Information
Please sign the “Speaker Sign-in Form” at the registration
desk. Note that the total time available for oral presentations
(other than plenary and special sessions) is 25 minutes, so
please check carefully the program for the time allocated to
your presentation. We recommend that you allow for 1 to 3
minutes for questions and discussion at the end of your talk.
Be alert, responsive, and respectful to other speakers when
the Session Chair signals you that you’ve got 5 and 2 minutes
remaining in your time slot. As a presenter you will be able
to use your own laptop or bring a memory stick. It is your
responsibility to check your presentation file for compatibility
with the Session Chair. We recommend that you seek out
and meet your Session Chair during the Conference Breakfast
(7-8am each morning), and to also meet with the Session
Chair at the presentation room 15 minutes before the session
begins. Please provide a brief biography (name, organization,
2-3 line description of current work assignment) to the session
chair prior to start of the session. Please check the signs and
handouts for further information. Please contact any of the
meeting organizers if you need help or have questions. You
will have a student assistant to assist you during the meeting.
You may use his/her assistance to drive the presentation,
help with A/V etc. Please check with the session chair and
the student assistant prior to the meeting.
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ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Meeting Rooms
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ANFM 2015 - Advances in Nuclear Fuel Management V
Monday March 30, 2015
Plenary Session
Palmetto Ballrooms A & B
8:00 AM
Pierre Paul Oneid
Senior Vice President & Chief Nuclear Officer
Mr. Pierre Paul Oneid is Senior Vice President and Chief Nuclear Officer of Holtec International and the
President of Holtec International subsidiary SMR, LLC. Mr. Oneid earned an Executive Master of Business Administration from Queens University in Canada in 1998 and a B.S. in Mechanical Engineering
from the University of Ottawa, Canada in 1981.
Dr. Russell Stachowski
Chief Consulting Engineer - Reactor and Nuclear Physics
Global Nuclear Fuel / GE Hitachi Nuclear Energy
Dr. Stachowski is Chief Consulting Engineer-Reactor and Nuclear Physics for GE Hitachi Nuclear Energy.
He has spent much of his career in the development, testing, licensing, and application of BWR fuel in
the US, Mexico, Japan and Europe. He has led the Nuclear Methods team in developing lattice and
core physics methods for BWRs. Russell holds a B.S. in Mechanical Engineering from the University
of Notre Dame and M.S. and Ph.D. degrees in Nuclear Engineering from the University of California,
Berkeley.
Ronald Jones
Vice President, New Nuclear Operations SCANA/SCE&G
Has primary responsibility to identify, evaluate and structure investments in the development of two
nuclear power plants from construction phase through commercial operation including completion of
design, construction, start-up, testing, design verification tests, inspections, and transitioning to an operating organization. Responsibilities include satisfying all Nuclear Regulatory Commission and state
and/or local governments’ requirements for the construction and operation of new nuclear power plants,
budgeting, financing and recruitment. Identifies, evaluates and hires outside contractors as needed
throughout all phases of development.
Brian R. Beebe
Director, Core Engineering, Engineering Center of Excellence, Westinghouse Electric Co.
Brian R. Beebe is the Director of Core Engineering in Westinghouse Electric Company’s Engineering
Center of Excellence. Westinghouse is the recognized world leader in the building of Nuclear Power
Electric Generating Plants, Operational Support for Nuclear Power Plants, Nuclear Fuel Development
and Supply and overall nuclear power generation research and development. Core Engineering has
the responsibility for the design and operational support of PWR and BWR reactors across the globe.
Brian is a three time recipient of the George Westinghouse Engineering Signature Award of Excellence,
a five time recipient of the Performance Excellence Award, and a graduate of the Westinghouse Customer First leadership Program. During his tenure at Westinghouse Brian has worked at many of Westinghouse’s facilities
worldwide including living for 2 years in Västerås, Sweden. Prior to joining Westinghouse Brian received his MS and BS
with High Honors in Nuclear Engineering from the University of Florida.
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ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
Meeting Room: Sabal
MM1 New Modeling Concepts, Reactivity Control, Generation of Cross Section Libraries and
Whole Core Transport Calculations
Chair: Hany Abdel-Khalik
10:00
60
Fuel Cycle Performance of Intermediate Spectrum Reactors with U/Th Feed and Continuous Recycling of U/TRU and Th/U3
Nicholas R. Brown Michael Todosow
Brookhaven National Laboratory, Upton NY
This paper documents fuel cycle analysis of an intermediate spectrum critical reactor with natural uranium and thorium as feed materials and continuous recycling of uranium
with transuranics and thorium with uranium (mainly 233U). The objective of the effort was to determine the impacts of both intermediate spectrum and U/Th feed versus the
reference fast spectrum and U-only feed case. In this context the intermediate energy regime is considered to be between 1 eV and 0.1 MeV. The potential benefits of
introducing thorium into the natural resource feed include extending the availability of uranium resources as well as potential operational/safety benefits, particularly related to
the void coefficient in some reactor designs. Two systems were analyzed at a near-equilibrium condition, a high void boiling water reactor with 54% of fissions occurring in the
intermediate energy regime and a D2O cooled pressurized water reactor with 65% of fissions occurring in the intermediate energy regime. The systems analyzed in this study
were determined to be self-sustaining at equilibrium when accounting for loss rates in fabrication and separations, and exhibit similar resource utilization when compared to a
fast system. Differences in performance versus a fast system are driven to some extent by the fact that eta for 233U and 239Pu at intermediate energies is never as high as
for 239Pu at fast energies.
10:25
75
Development of a Full-Core Reactivity Equivalence for FeCrAl Enhanced Accident Tolerant Fuel in BWRs
Nathan M. George (1), Jeffrey J. Powers (2), G. Ivan Maldonado (1), Andrew Worrall (2), Kurt A. Terrani (3)
1) Department of Nuclear Engineering, University of Tennessee Knoxville, TN, 2) Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, TN, 3) Fusion and Materials for Nuclear
Systems Division, Oak Ridge National Laboratory
The impact of replacing Zircaloy with a candidate iron-chromium-aluminum (FeCrAl) -enhanced accident-tolerant fuel (ATF) cladding material was evaluated for modern 10 ×
10 boiling water reactor (BWR) fuel bundles. The primary objective was to establish fuel design parameters for FeCrAl that match the reactivity lifetime requirements of
standard Zircaloy bundles. To compare the neutronic effects of these fuel alterations against standard UO2/Zircaloy fuel, a method based on 2D lattice physics was
established to estimate excess reactivity at the completion of each reactor operating cycle using a weighted fuel batch scheme. The methodology allows rapid scoping
studies to be performed prior to full-core simulations. An additional paper [1] presents the lattice physics and 3D full-core results verifying the reactivity equivalence method
for the alternate cladding fuel bundles.
10:50
89
Demonstration of a Full-Core Reactivity Equivalence for FeCrAl Enhanced Accident Tolerant Fuel in BWRs
Nathan M. George (1), Jeffrey J. Powers (2), G. Ivan Maldonado (1), Andrew Worrall (2), Kurt A. Terrani (3)
1) Department of Nuclear Engineering, University of Tennessee, Knoxville, TN, 2) Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge, TN, 3) Fusion and Materials for Nuclear
Systems Division, Oak Ridge National Laboratory, Oak Ridge, TN
The impact of replacing Zircaloy with a candidate iron-chromium-aluminum (FeCrAl)-enhanced accident-tolerant fuel (ATF) cladding material was evaluated for modern 10 ×
10 boiling water reactor (BWR) fuel bundles. Lattice physics calculations were completed with the 2D deterministic codes SCALE/TRITON and CASMO, and 3D full-core
calculations were performed with the NESTLE nodal diffusion code. The primary objective was to establish fuel design parameters for FeCrAl that match the reactivity lifetime
requirements of standard Zircaloy bundles. Due to the high neutron absorption of FeCrAl relative to standard Zircaloy, the FeCrAl cladding and channel box thicknesses were
decreased and the enrichment of uranium dioxide (UO2) fuel was increased. To compare the neutronic effects of these fuel alterations against standard UO2/Zircaloy fuel, a
method based on 2D lattice physics was established to estimate excess reactivity at the completion of each reactor operating cycle using a weighted fuel batch scheme. This
study is supported by a companion paper that thoroughly describes the established methodology [1]. With the cladding and channel box thicknesses halved, it was estimated
that an average enrichment increase of 0.6% 235U throughout the fuel lattice would be required. Verification of this 2D reactivity method was performed with a 3D full-core
parametric study. Matching the base UO2/Zircaloy cycle length of 527 effective full power days (EFPD) with UO2/FeCrAl required nearly the same fuel design adjustments in
full-core calculations as were predicted by the lattice physics results, thus demonstrating the accuracy of the reactivity method.
11:15
41
BWR Control Rod Mechanical Design Considerations Based on a Review of General Electric Control Rod Design and
Performance History
Scott Nelson
GE Hitachi Nuclear Energy, Wilmington, NC
A review of GE/GEH BWR control rod design and performance history is conducted from the original equipment to the present time. This review identifies common causes of
mechanical failures that are primarily attributed to Irradiation Assisted Stress Corrosion Cracking (IASCC). Identification of common causes allows for the establishment of
several design considerations that should be incorporated into future BWR control rod designs, for the purpose of reducing the likelihood of cracking. Finally, the GEH
UltraTM control rod design is reviewed, and the method by which each of the identified design considerations is incorporated into the new design is detailed.
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ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
11:40
81
Effect of Energy Group Structure on a Stylized European Pressurized Reactor (EPR) For Criticality Analysis
Daniel Lago and Farzad Rahnema
Nuclear & Radiological Engineering/Medical Physics Programs, Georgia Institute of Technology, Atlanta, GA, USA
This paper investigates the effect of energy group structure on a stylized MCNP model of the European Pressurized Reactor (EPR). A benchmark of the EPR was previously
developed purely for validation of transport methods. This study evaluates the cross sections generated by the lattice depletion code HELIOS for the EPR benchmark. This
paper describes the generation of problem-specific multi-group cross sections in 2-, 4-, 8-, and 47- group structures with HELIOS, as well as initial results from assembly level
MCNP calculations to evaluate the effect of group-collapsing. The paper also discusses the possible propagation of errors from the cross sections in whole-core calculations.
Meeting Room: May
MM2 Innovative Core Loading, Reload Design, and Licensing
Chair: Rodolfo Ferrer
10:00
7
Experience Developing Power Peaking Penalties for Fuel Assemblies Reconstituted with Stainless Steel Rods at Oconee
Nuclear Station
David Orr and Joy Forster
Duke , Charlotte, NC
Fuel assembly to core baffle interactions are a known phenomenon in the utility and vendor community. Currently at the Oconee Nuclear Station, which is owned and
operated by Duke Energy Carolinas, there are two primary fuel mechanical concerns involving fuel assembly to core baffle interaction: spacer grid wear and fuel rod wear.
While the mechanism of wear is different between the two issues, both may lead to concerns about the integrity of the fuel if no mitigating actions are taken. Hence, Duke
Energy has chosen to perform fuel assembly reconstitution—the insertion of stainless steel rods into fuel assemblies that already have resided in the core for at least one
cycle of operation—in a proactive fashion to mitigate the risk of fuel failures associated with these mechanisms of wear. The decision to reconstitute assemblies raises the
question of how to address the impact to power peaking and, subsequently, the validity of the safety analyses and maneuvering analysis for a given cycle with potentially 50
-60 stainless steel rods present in the core. One way is to create rod peaking penalties by modeling the affected fuel assemblies, including their burnup history, both with and
without the insertion of the stainless steel rods. A comparison is made between the predicted rod power peaking in both cases, and judgments may be made about
appropriate penalties to be applied in subsequent analyses.
10:25
8
Innovative Approach to Reloading an Initial Cycle
Jun Shi ,Samuel Levine, and Kostadin Ivanov
The Pennsylvania State University (PSU), University Park, PA
The objective of this paper is to present analyses of an innovative approach to reload an initial cycle loading pattern (LP) of a PWR by selecting the reload pattern fuel
assemblies, FAs, based on their K∞ rather than on their initial enrichment. In this new method, the FA K∞ is the primary selection factor, i.e., the FAs having the lowest K∞
are discarded after each cycle. However, it has been discovered that the sum of the 235U and the 239Pu nuclide’s number densities are also very important factors when
choosing the used FAs to be reloaded in cycle 2. The Haling Power Depletion (HPD) method has been extensively used to guide the design of the reload core. It was
discovered that the first cycle has to be the highest possible leakage core because of the nature of the condition of the end-of-cycle FAs. The HPD acceptable reload design
ended up with large loss in cycle length. In fact, the second cycle is also a relatively high leakage core. A more accurate step depletion calculation is implemented afterwards
to verify the design. The simple relative fuel cost comparison made between the two methods for the first reload cycle must now be made for the second cycle. Studies will
continue on reloading further cycles to obtain a long term understanding of minimizing the fuel cost.
10:50
14
On Multiobjective Optimisation Approaches for In-Core Fuel Management Optimisation
Evert B. Schlünz (1, 2), Pavel M. Bokov (1), Jan H. van Vuuren (3)
1) Radiation and Reactor Theory, Necsa, Pretoria, South Africa, 2) Department of Logistics, Stellenbosch University, Matieland, South Africa, 3) Department of Industrial Engineering, Stellenbosch University,
Matieland, South Africa
In the in-core fuel management optimisation (ICFMO) problem, a fuel reload configuration is sought which optimises the performance of a nuclear reactor, while also
satisfying prescribed operational constraints. ICFMO has been studied for several decades, initially as single-objective optimisation problems but in recent years also as
multiobjective optimisation problems. Several of the multiobjective ICFMO approaches adopted in the literature, however, exhibit serious shortcomings or drawbacks, and
very little research has been performed to address or overcome them. In this paper, we present a brief overview of the various multiobjective ICFMO approaches found in the
literature. We also provide a commentary on what we believe to be the most important shortcomings and drawbacks in these approaches and, concurrently, present our
suggestions for addressing them. The workability of these suggestions are demonstrated by their application to two test problems for the SAFARI-1 research reactor. The
results indicate that our suggested approaches are indeed feasible for multiobjective ICFMO problems. The aim of this paper is to encourage further research toward
multiobjective ICFMO via the inclusion of sound principles from the field of operations research.
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ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
11:15
17
The Greedy Exhaustive Dual Binary Swap Method for Fuel Loading Optimization Using the Poropy Reactor Optimization
Tool
Carl C. Haugen and Kord S. Smith
Massachusetts Institute of Technology, Cambridge, MA
This paper presents a deterministic optimization scheme termed Greedy Exhaustive Dual Binary Swap for the optimization of nuclear reactor core loading patterns. The goal
of this optimization scheme is to emulate the approach taken by an engineer when manually optimizing a reactor core loading pattern. This is to determine if this approach is
able to locate high quality patterns that, due to their location in the core loading solution space, are consistently missed by standard stochastic optimization methods such as
those in the simulated annealing class. This optimization study is carried out using the poropy tool to handle the reactor physics model. Optimizations of the full depletion
problem result in the deterministic Dual Binary Swap optimizer locating patterns that are of higher quality than those found by the stochastic Simulated Annealing optimizer,
with comparable frequency. The Dual Binary Swap optimizer is, however, found to be very dependent on the starting core conguration, and can not reliably nd a high
quality pattern from any given starting conguration.
Meeting Room: Palmetto B
MM3 PANEL Discussion - "Small Modular Reactors: Challenges and Proposed Solutions to
Successful Deployment"
Chair: Andrew Worrall
10:00
Objective of panel: To provide an insight from a number of perspectives as to the challenges facing the future deployment of Small Modular Reactors (SMRs), particularly of
the integral PWR (iPWR) variety. These challenges include technical, regulatory, economic, and supply chain issues. The intent is that the speakers identify the challenges
and propose solutions.
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ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
Meeting Room: Sabal
ME1 Error Quantification of Core Simulation Capabilities, Core Follow Data to Enhance Core
Simulation Fidelity, Utilization of Zero Power Physics Tests
Chair: Fausto Franceschini
4:20 PM
83
Tutorial Series on Characterization of Uncertainty (TUSC): Reduced Order Modeling, Dimensionality Reduction, Surrogate
Modeling, Function Approximation, Fitting, etc.
Hany S. Abdel-Khalik
School of Nuclear Engineering, Purdue University, West Lafayette, IN
The increased reliance on modeling and simulation for the analysis of complex engineering systems has made it essential to devise scientifically defendable approaches for
the characterization of uncertainties. The last two decades have witnessed the development of many reliable and efficient methods capable of identifying, quantifying,
prioritizing, and ultimately reducing the various sources of uncertainties. Despite the recent theoretical triumphs, it is safe to say that these developments are not readily
accessible by engineering practitioners who are the intended beneficiaries of these developments. This is because the subject of uncertainty characterization is heavily
mathematical in nature, which requires rigorous and abstract mathematical constructs to properly describe it in its most general form, which is the preferred approach by the
developers, mainly mathematicians and statisticians. While the rigor is definitely needed, it has made it extremely difficult for practitioners to understand the mechanics of the
various methods and independently evaluate their advantages and limitations, instead of relying on expert-judgment. The TUSC series intends to break this pattern by
introducing the material in a form more accessible by engineers and engineering practitioners. Our introduction will favor intuition over rigor, and will provide enough intuitive
arguments, as supported by reasonable amount of rigor, to help reveal the core ideas behind each method. This will enable engineers further develop and customize the
methods for their own needs. The present manuscript introduces the basic concepts and more importantly the distinguishing factors between reduced order modeling,
dimensionality reduction techniques, surrogate modeling; all basic ingredients of uncertainty characterization methods.
4:45 PM
87
Identifying Modeling Parameters to Influence an Operating Experience Observation
Atul A. Karve and Russell E. Stachowski
Global Nuclear Fuel, Wilmington, NC
Recent observations of a boiling water reactor reload cycle operation have reinforced the need for robust core simulator methods. Specifically, these methods can be
challenged in predicting operating parameters that are monitored by adaptive methods (derived core observables). To manage an unanticipated behavior in these derived
core observables, either excess conservatism in design needs to be incorporated and / or mitigating actions for adverse operation need to be exercised. Such actions are
undesirable because the excess margin and / or the operating changes can adversely impact the overall fuel cycle economics. Therefore, there is ever more need for
methods to be able to design the reload cycle (referred to as the offline prediction) such that when the reload cycle is operated closely as designed, the core monitoring
system (referred to as the online prediction) should be consistent with the offline, i.e. the derived core observables do not significantly depart from the design. Anomalies
occur when there is an unusual unexplainable deviation in the derived core observables. While it is reassuring that this is an isolated occurrence, the particular deviation
becomes an operating experience observation that needs to be further analyzed and studied. This paper attempts to do that for one such deviation – the derived core
observable relates to the maximum fraction of linear power density (MFLPD). In an INPO operating experience in 2014, the MFLPD was observed to significantly deviate
between the online and offline predictions. This study addresses that deviation by identifying specific causal factors in the modeling that can be adjusted to obtain the
observed effect. The purpose is to model the hypothesized behavior that the method can capture self-consistently. Such enhanced modification is not necessary to be
generalized; however, it attempts to capture plant specific operating variations (that are unknown) and / or embody realistic phenomena (that are known but possibly not
sufficiently modeled). In the end, this exercise identifies areas for further study to improve the prediction that could alleviate some of the operating uncertainty that needs to
be incorporated as part of the design.
5:10 PM
40
Core Follow and Cold Critical Calculations of Operation Cycles After Extended Outage in BWRs
Tsuyoshi Ama, Takashi Yoshii, Akihiro Fukao (1), Katsuyoshi Oyama (2)
Nuclear Core Engineering Dept., TEPCO SYSTEMS CORPORATION (TEPSYS), Koto-ku, Tokyo, Japan, 2) Nuclear Power Plant Management Dept. Tokyo Electric Power Company (TEPCO), Chiyoda-ku,
Tokyo, Japan
Core follow and cold critical calculations of several cycles including cycles after extended outage are performed for Japanese commercial BWRs using CASMO-4/SIMULATE
-3. The core follow calculation results and cold eigenvalues in cycle after extended outage are compared to those in cycles after normal outage. Hot eigenvalues and
traversing in-core probe (TIP) route mean square (RMS) errors are evaluated in the core follow calculation. The comparison shows that the change of reactivity caused by
extended outage is properly evaluated, and that the TIP RMS errors are similar between the cycles after normal outage and extended outage. The cold eigenvalues are also
evaluated in the cold critical calculation. The levels of cold eigenvalue in cycle after extended outage are similar to those in cycles after normal outage. These comparison
results show that CASMO-4/SIMULATE-3 is applicable to the evaluation in cycle after extended outage.
5:35 PM
74
Evaluation of the NPP Krško Core by JSI and Westinghouse Nuclear Analysis Codes
Marjan Kromar (1), Fausto Franceschini (2), Dušan Ćalić (1), Harish C. Huria (2)
1) Jožef Stefan Institute, Reactor Physics Division, Ljubljana, Slovenia, 2) Westinghouse Electric Company LLC, Cranberry Township, PA
Jožef Stefan Institute (JSI) and Westinghouse have performed reactor physics analysis of the several NPP Krško cycles using their respective core simulator packages, e.g.
CORD-2 and NEXUS/ANC 9. This paper shows the performance of each core simulator to predict the plant physics behavior, specifically analyzing the comparison vs.
measurements for the key core parameters. Critical boron concentrations, control rods worth and isothermal temperature coefficient are compared to the measured values.
The results show satisfactory performance from both code systems and their adequacy to support the core design calculations and fuel loading optimization for the Krško
NPP.
11
ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
Meeting Room: May
ME2 Modeling Methods, Advances in Reactor Stability and Fuel Temperature Feedback for
Steady-State and Transients
Chair: Vincent Penkrot
4:20 PM
10
Modeling Methods for Tightly Packed Granular Fuel
Abdalla Abou-Jaoude and Anna Erickson
Nuclear and Radiological Engineering Program, Georgia Institute of Technology
The paper investigates methods for modeling the neutronic behavior of fuels with Stochastic Granular Structures (SGS) to a high degree of fidelity and validates the models
against equivalent homogenized cases. Granular fuels have recently been the subject of renewed attention due to their many attractive properties and their design flexibility.
However, many fuels considered cannot reach high packing fractions, thus limiting their power density and heavy metal inventory. Developing and modeling fuels with higher
packing fractions is therefore very desirable. An algorithm was developed to closely replicate tightly-packed structures within a cylindrical container. MCNP6 simulations were
carried out using the obtained sphere coordinates and different metrics obtained were compared to homogenized models as well as models with simpler arrangements. The
results were in good agreement and validate employing this SGS modeling method when a more exact representation of the microstructure is required.
4:45 PM
78
Simulation of CASL 3D HFP Fuel Assembly Benchmark Problem with On-the-Fly Doppler Broadening in MCNP6
Scott J. Wilderman and William R. Martin (1), Forrest B. Brown (2)
1) University of Michigan, Department of Nuclear Engineering and Radiological Sciences, Ann Arbor, MI, 2) Los Alamos National Laboratory, Los Alamos, NM
An On-the-Fly Doppler broadening methodology has been applied in a neutronics simulation of a single fuel assembly (problem 6 of the CASL/VERA Core Physics
Benchmark Problems) using MCNP6. HFP temperatures and densities were taken from results of a coupled neutronic-TH computation with the neutron transport code
MPACT and the subchannel TH code COBRA-TF. An MCNP6 input file with over 13000 cells with independent temperatures and densities was constructed from a template
input file for CASL/VERA problem 3 (3D HZP full assembly). OTF Doppler broadening coefficients for the 54 unique isotopes of the problem were generated using the
routines provided in the MCNP6 distribution. HZP OTF MCNP6 results are compared with published benchmark results, and results for 3D HFP assembly simulations are
compared with neutronics results from the coupled MPACT/COBRA-TF simulation.
5:10 PM
66
Development of COBRA-TF for Modeling of Full-Core, Reactor Operating Cycles
Robert K. Salko and Travis Lange (1), Vefa Kucukboyaci, Yixing Sung (2), Scott Palmtag (3), Jess Gehin (1), Maria Avramova (4)
1) Oak Ridge National Laboratory, 2) Westinghouse Electric Company, 3) Core Physics, 4) The Pennsylvania State University
CTF, the Pennsylvania State University version of COBRA-TF, has been adopted as the subchannel thermal hydraulic (T/H) capability in the core simulator being developed
by the Consortium for Advanced Simulation of Light Water Reactors (CASL). This has resulted in significant development efforts to expand the applicability of CTF to
performing high-fidelity, full-core, multi-physics simulations. These efforts have focused on addressing CASL challenge problems for pressurized water reactors (PWRs),
which include modeling of departure from nucleate boiling and CRUD induced power shift. Developments specific to full-core modeling capabilities include creation of a
preprocessor utility for the user-friendly, rapid generation of pin-cell-resolved PWR models and implementation of a domain-decomposition parallelization of the code solution
algorithm. In preparation for modeling CRUD growth phenomena, a coupling interface has been developed for CTF and the code has been incorporated into a multistate
driver, which allows for modeling entire reactor operating cycles (i.e. years of operation). A simple CRUD modeling capability has been coupled to the code through this driver
for capturing CRUD growth over these long operational periods. This paper presents an overview of these new features and shows results of a full-core, pin-cell resolved
simulation of a Westinghouse 4-loop PWR core during a loss-of-flow transient as well as an initial coupled T/H-CRUD simulation of a 17 17 assembly during a 15-month
reactor operation cycle.
Meeting Room: Palmetto B
ME3 Advanced or Extended Fuel Cycles and Economic analysis
Chair: Craig Hove
4:20 PM
18
Updated Fuel Cycle Cost Model of the Fluoride-salt-cooled Hightemperature Reactor (FHR) Based on Neutronic
Calculations Using MC Dancoff Factors
Christopher Kingsbury and Bojan Petrovic
Georgia Institute of Technology, Nuclear and Radiological Engineering, Atlanta, GA
The Liquid Salt Cooled Reactor (LSCR), or Fluoride-salt High-temperature Reactor (FHR), is a type of Advanced High Temperature Reactor (AHTR), a generation IV reactor,
currently under development by Oak Ridge National Laboratory (ORNL) for the U. S. Department of Energy, Office of Nuclear Energy’s Advanced Reactor Concept Program.
The reactor design of 3400 MWt power employs graphite ‘planks’ filled with tristructuralisotropic (TRISO) fuel particles containing enriched uranium oxycarbide as fuel.
Expected higher fabrication costs of this fuel type, combined with the low heavy metal loading that challenges cycle length, make an accurate evaluation of fuel cycle cost and
characteristics very important. Our previous preliminary fuel cycle cost assessment employed multigroup (MG) burnup calculations in SCALE 6.1. However, the double
heterogeneity of the fuel elements was not completely accounted for. The use of Monte Carlo based (MC) Dancoff factors allows correcting for these inaccuracies. Using the
most recent fuel design specifications, appropriate MC Dancoff factors were calculated and applied. Use of these factors in MG depletion analysis yields corrected burnup
data for use in a preliminary FCC model, which, in turn, informs the fuel design to minimize the cost of electricity. The results acquired and put forth by this research show the
impact of the correction factors and identify an optimum fuel configuration under given assumptions.
12
ANFM2015 - Advances in Nuclear Fuel Management V
Monday, March 30, 2015
4:45 PM
57
24-month PWR Fuel Cycles - Two Decades of AREVA Design and Operating Experience
Craig Hove
AREVA Inc., Lynchburg, Virginia, USA
AREVA has over two decades of design and successful operational experience with 24-month nuclear fuel cycles for PWRs (and BWRs) in the USA. No safety, licensing or
equipment problems have occurred. Twenty-four month cycles increase cycle capacity factors, but fuel cycle economics should not be neglected. The most economical 24month cycles with efficient use of uranium that minimize the metric kg U235 feed / GWd thermal energy production require assembly designs with heavy U-metal loadings,
which is equivalent to low core power density in watts thermal per gram U-metal (w/g U-metal). For 24-month cycles, PWRs with high core power density (above 40 w/g Umetal) require very large inefficient feed batch sizes (i.e. large values of the metric kg U235 feed / GWd th) with degraded fuel cycle economics. The core power density can
be lowered by switching to an assembly design with heavy U-metal loading. The AREVA (B&W) plants operating in the USA and the AREVA EPR plants being built around
the world are all low power density cores and are thus very suited to economical 24-month cycles. For 24-month cycles, the UO2-Gd2O3 integral burnable neutron absorber
is needed to control reactivity and peaking to avoid supplementary removable burnable poison components and to minimize gas pressure buildup in fuel rods.
5:10 PM
55
Economic Assessment of Accident Tolerant Fuel Cladding Options
Nathan Andrews, Koroush Shirvan, Ed Pilat, Mujid S. Kazimi
Massachusetts Institute of Technology, Cambridge MA
If an accident tolerant fuel cladding is to replace the zirconium alloys, it will have to be economically viable. Four proposed materials are examined as cladding options:
Stainless steel (SS), FeCrAl alloy, molybdenum (Mo) tri-layer composite and silicon carbide ceramic matrix composite (SiC CMC), each having its own development time and
costs. The thickness of each cladding was assumed to reflect the strength of the material and its manufacturing limits. The UO2 enrichment savings or penalty was calculated
for each cladding option relative to Zircaloy, given unit costs from recent market conditions. Based on this analysis, it was found that all options may end up requiring higher
enrichment for the same fuel cycle length. SiC will likely be the least cost option. If the present value of avoiding a large reactor accident with a large radioactivity release is
estimated using past experience for LWR large accidents, there is a definite net economic benefit relative to typical Zircaloy cladding only in using SiC CMC as a cladding
material, when the ATF cladding is assumed capable of preventing reactor loss and radioactivity release in a Fukushima-type event. Because of the high enrichment costs
relative to accident costs, there is only a marginal economic benefit in using SiC to prevent a core-only loss without radioactivity release (TMI-type) accident and a large
economic loss using metallic ATF concepts.
5:35 PM
80
Nuclear Fuel Management Capacity Building Initiative for the Perspective of Introducing Nuclear Power in Morocco
Bouhelal Oum Keltoum
Higher National School of Mines of Rabat ENSMR Organization, Dept Industry Process, Rabat, Morocco
This paper gives a broad picture of the Moroccan nuclear program development and the benefit of launching nuclear power in the framework of the national energy planning
strategy and under the aegis of the IAEA. The paper describes the situation of the Moroccan energy sector and the current nuclear activities: although relevant efforts are
continuously made to consolidate the infrastructures that aim to enhance nuclear knowledge and international cooperation, the challenge posed by the nuclear fuel cycle
management for a newcomer country like Morocco remains today an important issue; better performing in building capacity is necessary and an example of upgrading
disciplines related to the nuclear fuel cycle management of the nuclear education program taught in the existing universities and engineering schools is proposed.
13
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
Room: Sabal
TA1 Core Analysis Tools for Fuel Management: Modeling and Validation - Part 1
Chair: Keith Drudy
8:00 AM
58
AP1000® PWR Startup Core Modeling and Simulation with VERA-CS
F. Franceschini (1), A. T. Godfrey, S. Stimpson, T. Evans, B. Collins, J. C. Gehin, J. Turner (2), A. Graham, T. Downar (3)
1) Westinghouse Electric Co. LLC, Cranberry Township, PA, USA, 2) Oak Ridge National Laboratory, Oak Ridge, TN, 3) University of Michigan, Ann Arbore
This paper describes the application of the Core Simulator of the Virtual Environment for Reactor Applications, VERA-CS, under development by the Consortium for
Advanced Simulation of LWRs (CASL) to the core physics analysis of the AP1000®1 PWR. The AP1000 PWR features an advanced first core with radial and axial
heterogeneities and at-power control rods insertion to perform the MSHIM™ advanced operational strategy. These advanced features make application of VERA-CS to the
AP1000 PWR first core especially relevant to qualify VERA performance. This paper focuses on the qualification efforts at hot zero power conditions, where Monte-Carlo
reference solutions have been established. The comparison of both global core parameters (e.g. critical boron concentration, rod worth and reactivity coefficients) and finemesh fission rate spatial distribution indicate excellent numerical agreement between VERA-CS and the Monte-Carlo predictions across the simulations performed.
8:25 AM
63
Two-Dimensional BWR Core Analysis using Multi-Assembly CASMO5 and SIMULATE5
Rodolfo M. Ferrer, Joshua M. Hykes, Joel D. Rhodes III (1), Tamer Bahadir (2)
1) Studsvik Scandpower, Inc., Idaho Falls, ID 83404-3345, USA, 2) Studsvik Scandpower, Inc., Waltham, MA
An analysis of a two-dimensional (2D) Boiling Water Reactor (BWR) using Multi-Assembly CASMO5 (C5) and SIMULATE5 (S5) is presented in this work. To model
representative conditions of a BWR core depletion in 2D, certain approximations are introduced and a methodology presented that allow users to verify the accuracy of the
nodal homogenized S5 model relative to a high-order, full-core transport results provided by multi-assembly C5. Previous assembly burnup and void history, as well as
instantaneous conditions such as fuel temperature and void distribution, may be consistently modeled in both codes using the approach presented in this paper. Numerical
results, which demonstrate the high level of accuracy achieved by the S5 nodal model relative to the reference fine-mesh transport solution obtained from C5, are presented
for a BWR cycle depletion.
8:50 AM
1
Improvements in TIP and Gamma Scan Predictions in the next Generation GNF BWR Core Simulator AETNA02
James E. Banfield, Tatsuya Iwamoto, Jason Mann
GE Hitachi Nuclear Energy (GEH)/Global Nuclear Fuel (GNF)
Global Nuclear Fuel (GNF)’s next evolution of advanced Boiling Water Reactor (BWR) simulator is the LANCER02/AETNA02 lattice physics/BWR core simulator. A state-ofthe-art lattice physics model using two-dimensional Method Of Characteristics (MOC) from LANCER02 is coupled with a three-group semi-analytic nodal method for core flux
solution in the AETNA02 core simulator, which is embedded within a flexible online core monitor system. AETNA02 includes a new model for in-core instrument response
calculations accounting for intra-nodal power tilt based on MCNP experience which is able to improve the fidelity of predicted Traversing In-core Probe (TIP) signals,
particularly for gamma TIP plants, as well as thermal TIP plants. This TIP response model is described and studied within the advanced lattice-physics and core-simulator
system LANCER02/AETNA02. In this paper, several plants from the GNF database will be examined and compared to PANAC11 TIP response predictions. Substantial
improvement over the previous TIP response model predictive capability is demonstrated in this paper. In addition, pin-by-pin gamma scan comparisons will be presented
which also demonstrate the integral effect of both lattice physics and core physics modeling on fidelity compared to physical measurement. The impact of each new model in
AETNA02 including the three-group flux solution, the new thermal hydraulic model, the multi-blade and blade depletion feedback, as well as the new TIP model will be
studied separately as well as in combination to see the breakdown of improvement as well as the integral improvement. Accuracy in instrument response predictions is a
critical part of the amount of adaption necessary and on the reduction of on-line/off-line biases and operational stability. Accuracy in the pin power predictions is closely
related to uncertainties used in the establishment of thermal limits.
Room: May
TA2 Nodal and Lattice Physics Methods - Part 1
Chair: Scott Palmtag
8:00 AM
45
Improved PWR Radial Reflector Modeling With SIMULATE5
Tamer Bahadir
Studsvik Scandpower, Inc., Waltham, MA
The recent improvements implemented in Studsvik’s next generation code package CMS5, with CASMO5 and SIMULATE5, in modeling the PWR radial baffle/reflector is
presented in this work. The shortcomings in the conventional approach of generating radial homogenized cross-sections and discontinuity factors from a 1D fuel/reflector
transport calculation have been eliminated by re-computing the reflector node cross-sections and discontinuity factors in real core geometry by using the submesh calculation
model in SIMULATE5. The submesh constants for the radial reflectors are generated from either a 1D fuel/reflector transport calculation or a multi-assembly core transport
calculation. The effects of radial reflector modeling on core eigenvalue and assembly power predictions are demonstrated for the BEAVRS benchmark problem.
14
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
8:25 AM
20
Westinghouse Development and Customer Support for the New Core Analysis and Design System
Vincent S. Penkrot, William A. Boyd, Baocheng Zhang, and Kevin T. Lasswell
Westinghouse Electric Company, Cranberry Township, Pa
Westinghouse Electric Company has developed its next-generation core analysis and monitoring software products. This new code set more tightly integrates the ANC core
simulator and the BEACON™ Core Monitoring System*. Additionally, Westinghouse has developed a new system for nuclear data generation named NEXUS. Westinghouse
recognized that the development of this new system, which replaces the ALPHAPHOENIX- ANC (APA) and BEACON version 6 systems, required not just a software
development effort, but a complete utility transition effort including training and licensing support. This system is now in use by a number of US and international utilities. This
paper will describe the features of the NEXUS system, updates to ANC in version 9, integration of ANC version 9 and BEACON version 7 as well as support tools used by
Westinghouse to assist utility transition.
8:50 AM
21
Southern Nuclear’s Implementation of Westinghouse’s Next Generation Core Design Simulator and Core Monitoring
Software
Robin D. Jones (1), Gary T. Wolfram (2)
1) Southern Nuclear Operating Company, Birmingham, AL, 2) Westinghouse Electric Company, Rock Hill, SC
The Southern Nuclear Operating Company (SNC) has been working with Westinghouse Electric Company (WEC or Westinghouse) on early implementation of a tightly
integrated ANC (ANC9) core simulator and the BEACON™ Core Monitoring Software Version 7 (BEACON7) core monitoring system as well as the development of a new
system for nuclear data generation named NEXUS. This paper will describe SNC efforts to support Westinghouse in the development, debugging, benchmarking and final
implementation of the new methodologies at the Farley and Vogtle units. SNC has also developed ANC9 models for the Vogtle 3 and 4 cores. These models have the unique
features of the integrated ANC9 system needed to support the modeling of the new Westinghouse AP1000 reactor design. In addition, this paper will describe some of the
difficulties experienced in the long implementation process and outstanding issues.
9:15 AM
22
Finite Difference Method with Corrective Coupling Coefficient for Neutron Diffusion Calculation of Nuclear Reactor Core
Analysis
Jae-Seung Song and Jin Young Cho
Korea Atomic Energy Research Institute, Yuseong-gu, Daejeon, Korea
A finite difference method with a single radial mesh per fuel assembly, of which interface coupling coefficients are corrected using the information obtained from threedimensional whole core transport calculation, is proposed to solve the neutron diffusion equation for the nuclear reactor core. The nodal group constant for each mesh and
the corrective interface coupling coefficient for each interface are tabulated as functions of the parameters affecting the neutron spectrum such as the soluble boron
concentration, the fuel temperature and the moderator density. The method is tested through a core calculation for the pressurized water reactor, based on comparisons of
the power distribution and the effective multiplication factor with those of a three-dimensional whole core transport calculation.
Room: Palmetto B
TA3 Advanced Fuel Management, Multi-dimensional Burnup Analysis, and Depletion
Chair: Bojan Petrovic
8:00 AM
64
Methodology of the On-Line Fuel Management of Pebble Bed High Temperature Reactors Including Follow and Prediction
Methods
Bing Xia and Fu Li, Chunlin Wei, Jian Zhang, Jiong Guo
Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Tsinghua University, Beijing, China
The on-line fuel management is an essential feature of the pebble-bed high-temperature reactors (PB-HTRs), which is strongly coupled with the normal operation of the
reactor. For the purpose of on-line analysis of the continuous shuffling scheme of numerous fuel pebbles, there are two kinds of calculations necessary for the PB-HTRs, i.e.
the on-line follow calculations and prediction calculations. The keys of on-line follow calculations are the decoupling of pebble flow and steady-state neutronics calculations
and the discretization of core layout and operation history. Based on the core status at a certain moment, a series of prediction calculations are implemented, and the best
estimate of future operation scheme is made by polynomial interpolations. Both calculations are carried out by using the VSOP code system, and verified by the actual
operation data of the HTR-10.
8:25 AM
25
Whole Core Analysis of Molten Salt Breeder Reactor
Jinsu Park, Yongjin Jeong, and Deokjung Lee
Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
The simulation of whole core depletion and continuous reprocessing of Molten Salt Breeder Reactor (MSBR) has been performed. The MSBR model was built using MCNP6
and the depletion and reprocessing simulations were modelled using CINDER90 and PYTHON script. The PYTHON script was introduced to implement online reprocessing
of molten-salt fuel and feeding of new fertile material with 3-day depletion intervals during the simulations. The simulation starts with the reference composition from the
original ORNL MSBR design [3] and equilibrium compositions are searched through the depletion and reprocessing simulations for 1200 days. The MSBR whole core
analysis was performed at the initial and equilibrium core conditions, for various reactor design parameters such as multiplication factors, neutron flux distributions,
temperature coefficients, rod worths, and power distributions. The neutronic core characteristics was analyzed using four factor formula applied to the two zones of the core
separately.
15
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
8:50 AM
49
Design of a Fast Breed/Burn Reactor Core Using the Deterministic Code KANEXT
Roberto Lopez-Solis and Juan Luis Francois-Lacouture
Universidad Nacional Autónoma de México, Facultad de Ingeniería, Morelos, México
Fast breeder reactors are an interesting type of nuclear systems, due to, given the correct design conditions, they can generate more fissile fuel than they consume;
nevertheless, in order for that breed fuel to be usable, it must be extracted from spent fuel an reprocessed before being used in the fabrication of new fuel. On the other hand,
in a Breed/Burn reactor (B&B), bred plutonium is burned “in situ”, inside the core, just after being bred; this reduce costs and fuel proliferation by simplifying the fuel cycle. In
this work, we present a B&B reactor design consisting of 210 active fuel assemblies plus 7 spaces for control rod assemblies. This core differs from most of the B&B reactors
in its design that include a blanket zone in the center of the core; this is to take advantage of the population of fast and epithermal neutrons in the center of geometry, due to
the fissions in adjacent zones. A satisfactory fuel reshuffling scheme was found in which the reactor operated for about 38 years, about 10 years more of what would have
operated without any reshuffling scheme. Regarding the tool for the full core calculations, KANEXT code was used. Since this is a deterministic code, hardware needs were
easy to satisfy and computational time was suitable for this kind of trial and error repetitive fuel reshuffling tests.
16
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
Room: Sabal
TM1 Core Analysis Tools for Fuel Management: Modeling and Validation - Part 2
Chair: Bob StClair
10:00
15
Optimizing the In-Core Fuel Management of BWRs using Rosa
L Gilli and P H Wakker
NRG Utrechtseweg 310, Arnhem, The Netherlands
The in-core fuel management of a nuclear reactor is a challenging task due to the virtually infinite number of possible loading patterns one could theoretically adopt. The
ROSA (Reloading Optimization by Simulated Annealing) code is an optimization tool that has been successfully used in the last couple of decades to facilitate the core design
of several Pressurized Water Reactors. In this paper we discuss the ongoing development of a version of ROSA capable of performing the core design of Boiling Water
Reactors. We focus the discussion on the modifications of the neutronic module of the code that are needed to improve the accuracy when performing depletion calculations
of BWRs.
10:25
69
Pellet-Cladding Mechanical Interaction Analyses Using VERA
B. T. Mervin, M. L. Pytel, D. F. Hussey, and S. M. Hess
Electric Power Research Institute, Palo Alto, CA
A CASL Test Stand was launched in 2013 to evaluate VERA’s fuel performance component, BISON-CASL, as a state-of-the-art fuel performance code for PCI analysis by
guiding it through a series of fuel performance progression problems. The progression problems are performed using 2D R-Z axisymmetric models and focus on examining
the thermal and mechanical responses of the fuel and cladding to an imposed axially-varying power history. The progression begins with a constant axial power profile
imposed during a single cycle ramp up to power followed by steady-state operation for a short length test rod and concludes with the most complex case studied by the Test
Stand: a full-length fuel rod with an axially-varying power history containing a first cycle ramp to full power steady-state operation followed by a shutdown and a second-cycle
ramp to full power. The evaluation of these progression problems is performed by comparing BISON-CASL results against results from the Falcon fuel rod performance code.
The results of this comparison show that while differences exists in the thermomechanical responses between the two codes, the peak inside cladding surface hoop stress
calculated by the two codes are within 0.5% of one another.
10:50
85
Physics-guided Coverage Mapping (PCM): A New Methodology for Model Validation
Hany S. Abdel-Khalik (1) and Ayman I. Hawari (2)
1) School of Nuclear Engineering, Purdue University, West Lafayette, IN, 2) Department of Nuclear Engineering, North Carolina State University, Raleigh, NC
This manuscript deals with a fundamental question in model validation: given a body of available experiments and an envisaged domain of reactor operating conditions
(referred to as reactor application), how can one develop a quantitative approach that measures the portion of the prior uncertainties of the reactor application that is covered
by the available experiments? Coverage here means that the uncertainties of the reactor application are originating from and behaving in exactly the same way as those
observed at the experimental conditions. This approach is valuable as it provides a scientifically defendable criterion by which experimentally measured biases can be
credibly extrapolated (i.e., mapped) to biases for the reactor applications. This manuscript introduces a novel approach, referred to as physics-guided coverage mapping
(PCM) which provides a natural solution to this problem by relying on high fidelity physics simulation. We discuss the potential advantages of PCM over the methods of
similarity indices, data assimilation, and model calibration commonly employed in the nuclear community.
11:15
23
A Method to Optimize Robust Core Design Performance Based on Design for Six Sigma (DFSS) Methodology
Serkan Yilmaz
Global Nuclear Fuel – Americas, Wilmington, NC
This paper provides the detailed information about the methodology of newly developed Robustness Evaluation Module of ePrometheus. It summarizes the background and
motivation of the work, Robust Core Design Description based on Design For Six Sigma (DFSS) methodology, design basis assumptions, historical simulation uncertainties in
the reactor operations, development of robustness methodology and robustness metric for optimization response surfaces, opportunities and defect definition based on
robustness performance and calculate statistical long-term process capability predictions based on DFSS methodology. A new ePrometheusTM prototype has been
developed and incorporates this method as a modular functionality.
11:40
24
Optimizing the Outage Refueling Time with Shuffle Conscious Core Design Evaluation via ePROMETHEUS™
Serkan Yilmaz (1), John A. Elam (contributor) (2)
1) Global Nuclear Fuel – Americas, Wilmington, NC, 2) Nuclear Engineering Consultant, Leland, NC
This paper provides the detailed information about the methodology of newly developed Robustness Evaluation Module of ePrometheus™. It summarizes the background
and motivation of the work, Robust Core Design Description based on Design For Six Sigma (DFSS) methodology, design basis assumptions, historical simulation
uncertainties in the reactor operations, development of robustness methodology and robustness metric for optimization response surfaces, opportunities and defect definition
based on robustness performance and calculate statistical long-term process capability predictions based on DFSS methodology. A new ePrometheusTM prototype has been
developed and incorporates this method as a modular functionality.
17
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
Room: May
TM2 Nodal and Lattice Physics Methods - Part 2
Chair: Steve Bowman
10:00
50
Comparative Neutronics Analysis of DIMPLE S06 Benchmark
Wonkyeong Kim, Jinsu Park, Deokjung Lee (1), Tomasz Kozlowski (2)
1) Ulsan National Institute of Science and Technology- UNIST, Ulsan, Republic of Korea, 2) University of Illinois, Urbana-Champaign, USA
The DIMPLE S06 critical benchmark has been calculated using a direct modeling and a two-step modeling approaches. A direct modeling is performed with MCNP6,
SERPENT2, CASMO4E, and TRITON/NEWT. A two-step modeling is performed by using the nodal code PARCS3.0 employing the homogenized two-group cross section
which are generated through SERPENT2, CASMO4E and TRITON/NEWT. Detailed calculation models are developed in this paper and the parameters for a two-step
modeling generated by each code are compared to each other. Finally, the eigenvalue for DIMPLE S06 are compared to each a direct and a two-step modeling. In this paper,
the calculation result of two-step modeling agrees well with that of direct modeling. The result shows that the use of the assembly discontinuity factor in two-step calculation is
essential to improve the relative error to the result of a direct modeling. A necessity of the assembly discontinuity factor is clearly proved by calculating the flux distribution for
the homogenized assembly.
10:25
47
CASMO5 Analysis of NCA Tungsten Critical Experiments
Joshua Hykes and Rodolfo Ferrer
Studsvik Scandpower, Inc., Idaho Falls, ID
This analysis of a series of critical experiments demonstrates the accuracy of CASMO5’s predicted fission rate distributions in the presence of tungsten gray control rods,
which are inserted during operation of the AP1000 PWR. The RMS error of the computed fission rate range between 0.007 and 0.014 over the five core configurations, with a
maximum absolute di erence of 0.025. This compares favorably with the quoted 2% standard deviation in the measurements. Comparison of identical 2D CASMO5 and
MCNP6 models of the cores reveals excellent agreement for the core multiplication factors, within 100 pcm when using CASMO5’s 586 energy group structure.
10:50
2
Automated Reactor Records Evaluation Framework
Jonatan Hejzlar and Frantisek Havluj
Reactor Physics Department, UJV Rez, s.r.o.
Plant operational data evaluation has a key role in the core physics code validation process. However, the amount of the data coming from the reactor operation is often so
vast that it can be discouraging for the code developers to use it properly, often resulting in a reduction of the data set used which may easily introduce bias into the
uncertainty quantification rendering the uncertainty results questionable. We present an elaborate, fully automated framework, which we have designed and implemented in
our institute, for reactor records processing and its use for core physics code validation. Through a high level of automation this framework resolves the many difficulties in
dealing with operational data giving easy and painless access to all the reactor records. This framework has been used for the validation of our ANDREA v2.0 core physics
code before the Czech nuclear regulatory body. It has shown to be a powerful tool for comparing various code and library versions between themselves. It has also shown to
be a tool useful for the validation of the received data itself.
11:15
82
CRANE: A New Scale Super-Sequence for Neutron Transport Calculations
Congjian Wang and Hany S. Abdel-Khalik (1), Ugur Mertyurek (2)
1) School of Nuclear Engineering, Purdue University, West Lafayette, IN, 2) Oak Ridge National Laboratory, Oak Ridge, TN
A new “super-sequence” called CRANE has been developed to automate the application of reduced order modeling (ROM) to reactor analysis calculations under the SCALE
code environment. This new super-sequence is designed to support computationally intensive analyses that require repeated execution of flux solvers with variations in
design parameters and nuclear data. This manuscript provides a brief overview of CRANE and demonstrates its applications to representative reactor physics calculations.
Specifically, two ROM applications are demonstrated, the intersection subspace-based approach for uncertainty quantification which is intended to reduce the number of
uncertainty sources in a conventional uncertainty analysis, and the exact-to-precision generalized perturbation theory methodology intended as a physics-based surrogate
model to replace the flux solver, i.e., NEWT. Our overarching goal is to provide a prototypic ROM capability that allows users to further explore and investigate the benefits of
using ROM methods in their respective domain and help guide further developments of the methodology and evolution of the tools.
18
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
Room: Palmetto B
TM3 PANEL Discussion - "Adequacy of Methods for Nuclear Fuel Management”
Chair: Jeffrey R. Secker
10:00
The panel discussion “Adequacy of Methods for Nuclear Fuel Management” will discuss the state of methods currently used for LWR reload fuel design and fuel
management. Representative from all US vendors as well as a major software vendor are on the panel along with experts from academia and a national lab. Status of current
methods and plans for future methods development will be discussed. Questions from the audience are welcomed.
Panelists:
Paul Turinsky, NC State University
Jess Gehin, Oak Ridge National Lab
Keith Drudy, Westinghouse Electric Co
Tamer Bahadir, Studsvik
Russ Stachowski, Global Nuclear Fuel
Kevin Segard, Areva
19
ANFM2015 - Advances in Nuclear Fuel Management V
Tuesday, March 31, 2015
Room: Sabal
TE1 Thorium Cycles, MOX utilization, and Plutonium Disposition
Chair: Ron Ellis
4:20 PM
19
Performance of Thoria Fuels and SiC Cladding for Burning of Plutonium in Pressurized Water Reactors
Yanin Sukjai and Mujid S. Kazimi
Massachusetts Institute of Technology, Cambridge, MA
For burning of excess weapons plutonium in nuclear reactors, thorium is a better host fuel, since it does not generate new plutonium as uranium does, thus allowing faster
depletion of the Pu stockpile. In this study, we compare the performance of two types of fuel materials (UO2-PuO2 & ThO2-PuO2) and two types of cladding (Zircaloy-4 &
SiC) during irradiation, given a certain power history and axial peaking factors generated from full-core neutronic simulation. ThO2 has higher thermal conductivity and lower
fission gas release rate than UO2. Thus, it is expected to enable better fuel performance during irradiation.
Compared to zirconium based cladding, silicon carbide (SiC) has several desirable characteristics such as higher melting point, lower neutron absorption cross-section and
better corrosion resistance. However, the low thermal conductivity of irradiated SiC and lack of creep down towards the fuel lead to a higher fuel temperature during
irradiation. To reduce the high fuel temperature, the possibility of replacing the fuel-cladding gap bond material with lead bismuth eutectic (LBE) or high thermal conductivity
porous foam is investigated.
FRAPCON 3.4 was modified to allow the simulation of all these variants, and used to assess the best approach to Pu burning in PWRs. The results indicate that thoria
reduces fission gas release compared to urania, thus reducing the internal fuel rod pressure. In addition, a foam bond material, such as alumina or graphite, will further
reduce the temperature of the fuel with SiC cladding, and enable better fuel performance.
4:45 PM
9
The TRU-Incinerating Thorium RBWR Core Preliminary Design
Phillip Gorman, Sandra Bogetic, Guanheng Zhang, Massimiliano Fratoni, Jasmina Vujic, and Ehud Greenspan
University of Berkeley, California
This study searches for the optimal design for the RBWR-TR – a reduced moderation BWR with a high transuranic (TRU) consumption rate. It is charged with LWR TRU and
thorium and recycles all actinides unlimited number of times while discharging only fission products and trace amounts of actinides. This design is a variant of the Hitachi
RBWR-TB2, which arranges its fuel in a hexagonal lattice, axially segregates seed and blanket regions, and fits within an ABWR pressure vessel. The RBWR-TR eliminates
the internal axial blanket, eliminates absorbers from the upper reflector, and uses thorium rather than depleted uranium as the fertile makeup fuel. The design variables of the
parametric studies include the fuel pitch-to-diameter ratio, number of fuel rods per assembly, length of each fuel section, TRU feed fraction, coolant flow rate, and fuel
residence time. The sensitivity of the void feedback, cycle length, burnup, TRU consumption efficiency, shutdown margin, and critical power ratio to variation in each of the
design variables were quantified to guide the design. A design is presented which incinerates TRU at a slightly higher rate per GWeY and discharged significantly less
plutonium of a smaller fissile fraction than the reference ABR and RBWR-TB2 while meeting all the design constraints. However, due to significantly lower discharge burnup
the RBWR cores require significantly larger reprocessing and fuel fabrication capacity per GWeY than the reference ABR.
5:10 PM
52
Comparison of Thorium and Uranium Fuel Performance in VVER-1000 Reactor
Jan Frybort
Czech Technical University in Prague, Department of Nuclear Reacors, Prague, Czech Republic
Thorium can be considered as an alternative to uranium fuel. This analysis deals with ThO2 fuel for Pressurized-Water Reactor VVER-1000 and its comparison to UO2.
Operational and spent fuel characteristics are considered. The main advantage of thorium is limited production of minor actinides and its greater abundance in nature.
Problem of thorium utilization is absence of a fissile nuclide in the natural thorium, thus thorium fuel needs to be supported by an added fissile material. Addition of 233U and
low-enriched uranium with 19.75 % enrichment is considered. The analysis is carried out using ANDREA nodal code with diffusion data prepared by HELIOS calculations.
Room: Palmetto B
TE3 PANEL Discussion - "Ongoing Fuel Performance and Fuel Cycle Issues - Driving to Zero"
Chairs: Rob Schneider & Paul Cantonwine
4:20 PM
The panel discussion “Ongoing Fuel Performance and Fuel Cycle Issues: Driving to Zero:” will cover a variety of operational issues for fuel in both BWR and PWR reactor
designs such as fuel reliability, BWR channel distortion and the benefits of annual cycles to fuel cycle costs. The perspective of both BWR and PWR fuel vendors and
experienced plant operators will be provided by the panelists.
Panelists
Rob Schneider, Global Nuclear Fuel
Paul Cantonwine, Global Nuclear Fuel
Brian Beebe, Westinghouse
Jim Tusar, Exelon
Bill Herwig, SCE&G
20
ANFM2015 - Advances in Nuclear Fuel Management V
Wednesday, April 1, 2015
Room: Sabal
WA1 Automated and Interactive Fuel Management Design and Optimization Tools - Part 1
Chair: Gerardo Grandi
8:00 AM
61
Recent Developments of the ROSA PWR Code and a Special Loading Pattern Design Application
F.C.M. Verhagen, H.P.M. Gibcus, P.H. Wakker (1), D. Janin, M. Seidl (2)
1) NRG, Arnhem, The Netherlands, 2) E.ON Kernkraft GmbH, Hannover, Germany
The core-loading pattern is decisive for fuel cycle economics, fuel safety parameters and economic planning for future cycles. ROSA, NRG’s loading pattern optimization
code system for PWRs, has proven to be a valuable tool to reactor operators for almost two decades for improving their fuel management economics in a more and more
constrained environment. ROSA uses simulated annealing as loading pattern optimization technique, in combination with an extremely fast 3-D neutronics code for loading
pattern calculations. The code is continuously extended with new optimization parameters and other functionality. This paper outlines recent developments of the ROSA code
system with a focus on the new full core version, DNBR-capability, and a special End Of Life (EOL) loading pattern design application.
8:25 AM
46
Detailed VIPRE Core Models from SIMULATE-3K
Gerardo Grandi and Jerry Judd
Studsvik Scandpower, Inc., Idaho Falls, ID
In depth analysis of Reactivity Initiated Accidents (RIA) and plant transients in Pressurized Water Reactors (PWR), requires the integration of many different analytical tools.
One such tool, the 3D nodal transient code SIMULATE-3K1 (S3K) has been coupled with the system codes RELAP5-3D,2 RELAP5-Mod3.33 and TRACE,4 to provide a bestestimate coupled code system for performing plant transient calculations with reactivity feedback from a detailed core model.5,6 More recently, S3K has been coupled with
the fuel performance code ENIGMA.7 The combination of these two codes provides a powerful analytical tool for the analysis of RIA.8 In line with these previous
developments, one would like to be able to have an in-depth analysis of the fuel assemblies Thermal-Hydraulic (TH) performance during RIA and plant transients. The first
step in this direction is the interface between S3K and VIPRE.9 The purpose of this paper is to describe the status of the S3K/VIPRE interface and to show its application to a
Rod Ejection Accident (REA) scenario.
8:50 AM
54
Designing Optimized Shuffles with SOSA
P.H. Wakker, H.P.M. Gibcus and F.C.M. Verhagen
NRG, Arnhem, The Netherlands
SOSA is NRG’s software package for design and optimization of fuel shuffles. SOSA is focused on shortening the reload time of the reactor core. By reducing the movements
of the refueling machine to a minimum, the reload time can be shortened by as much as 6-8 hours. This paper describes a few of the code’s features, such as the way to
divide a shuffle into segments or phases, the approach to guarantee sufficient SDM, possibilities for spent fuel pool optimization and SOSA’s capability for generating move
sheets. Finally, a couple of recently obtained results for different nuclear power plants are summarized.
9:15 AM
68
A New MIP Based Loading Pattern Search Tool
Frank Popa
Westinghouse Electric Company LLC, Cranberry Township, PA
The Pearls™ loading pattern search tool has generated reactor core loading patterns with significant fuel cycle cost benefits over the years. This mixed integer linear
programming (MILP) based tool has worked well for so called standard loading pattern searches. A new tool (TNT) is under development at Westinghouse that will build on
the success of Pearls and on the once through cross section capability of NEXUS but will remove the limitations of Pearls. This will again be a MILP based method. TNT will
handle the full panoply of objective functions and constraints. All PWR currently used burnable absorbers will be included. One particularly difficult aspect of loading pattern
search is the choosing of the feed pattern. Two very different feed patterns may yield near optimum loading patterns once all the other decisions are made. An unusual
feature of this new tool is that it systematically and exhaustively analyzes all feed patterns within the MILP framework. The expectation is then that the final loading patterns
will be global optima within the accuracy of the associated licensed reactor core neutron flux solver.
Room: May
WA2 Advanced Fuel Assembly and Burnable Absorber Designs
Chair: Christian Malm
8:00 AM
11
Neutronic and Economic Evaluation of Accident Tolerant Fuel Concepts for Light Water Reactors
Ian Younker (1), Massimiliano Fratoni (2)
1) The Pennsylvania State University, University Park, PA, 2) University of California, Berkeley, CA
Ceramic clad coatings and alternative cladding materials are a few of many accident tolerant fuel (ATF) concepts. Each concept looks to reduce the amount of zirconiumalloy cladding available for reaction with high temperature steam. In order to be implemented into current and future light water reactors (LWR), ATF concepts must provide
enhanced neutronic and economic performance over conventional Zircaloy-UO2 fuel. This study used a single assembly pressurized water reactor (PWR) model to
investigate reactivity drop, cycle length penalty, enrichment compensation, and reactivity coefficients, and a fuel cost model to understand economic performance. Findings
show a desirable thickness of 10-30 μm for ceramic clad coatings to reduced neutronic economic penalties. For alternative cladding materials, SiC accommodates thicker
cladding while other alloys, due to large neutronic penalties, require thin tubes and/or higher enrichment.
21
ANFM2015 - Advances in Nuclear Fuel Management V
Wednesday, April 1, 2015
8:25 AM
59
A Full Core Integral Fuel Performance Assessment of SiC Cladding
Alexander J. Mieloszyk, Ronald Gil, Koroush Shirvan, Mujid S. Kazimi
Massachusetts Institute of Technology, Center for Advanced Nuclear Energy Systems, Cambridge, MA
To better understand the implications of using SiC cladding in a commercial reactor, a framework has been developed to evaluate the fuel performance of a large fraction of
the fuel rods in a typical PWR core. This framework makes use of the newly developed RedTail fuel performance code and the CASMO-SIMULATE reactor physics suite.
Applying current component specific material properties, this framework is utilized to assess a three-layer SiC cladding design and compare it to the performance of
zirconium-based clad fuel under the same conditions. This assessment reveals higher fuel temperatures and plenum pressures associated with the SiC cladding, similar to
those observed in previous single pin analyses. Of note, however, is the observation that the SiC cladding stresses increase significantly during reactor shutdowns due to the
presence of radial gradients of swelling (growth) strain. Additionally, the hottest and most burnt fuel rods do not present the most challenging conditions to the SiC clad fuel.
This implies that a capability to analyze the fuel performance of an entire core is necessary to find the expected cladding failure risk associated with the deployment of various
SiC cladding designs.
8:50 AM
53
Accident Tolerant Fuel and Resulting Fuel Efficiency Improvements
Jeffrey Secker, Fausto Franceschini, and Sumit Ray
Westinghouse Electric Company, LLC, Cranberry Township, PA
Fuel designs using advanced, accident tolerant fuel materials can improve fuel efficiency and extend fuel management capability in addition to improving safety margins for
LWRs. The use of SiC cladding material can reduce fuel cycle costs by about 2% if it can be manufactured to the current thickness of zirconium alloy based cladding in use in
PWRs today. The increased pellet densities associated with the higher density U3Si2 or UN material also can reduce fuel costs by an additional 4-6% beyond the SiC cost
reduction for 18 month cycles or 8-11% for 24 month cycles. Because of the increased density, the use of these materials also extends the energy output and cycle length
capability for PWR fuel assemblies while remaining below the 5 w/o enrichment limit for commercial fuel and can make 24 month cycle operation economical for today’s
uprated, high power density PWRs.
Room: Palmetto B
WA3 PANEL Discussion - "CASL: Consortium for the Advanced Simulation of Light Water
Reactors"
Chairs: Paul Turinsky (NC State University), Rose Montgomery (Tennessee Valley Authority)
8:00 AM
The Consortium for Advanced Simulation of Light Water Reactors (CASL) is an Energy Innovation Hub established by the US Department of Energy in 2010 to advance the
development and application of modeling and simulation technologies for nuclear reactors. CASL’s mission is to provide a step change in computational capabilities to the
nuclear energy industry—one that enables more accurate prediction of the key phenomena defining the operational and safety performance of light water reactors (LWRs).
Through CASL, experts from national laboratories, universities, and industry are developing and deploying CASL’s Virtual Environment for Reactor Applications (VERA), a
“virtual reactor” designed to accurately simulate the physical processes inside a reactor at unprecedented levels of detail. These processes include neutron transport, thermal
hydraulics, nuclear fuel performance, and corrosion and surface chemistry. VERA relies on the latest science-based physical models for nuclear reactor phenomena,
advanced numerical methods for solution of these models, modern computational science and engineering techniques for imparting these methods into the VERA software,
tools for estimating uncertainties and sensitivities of the VERA simulations, and validation against data from operating reactors and other pertinent experiments. More
information is available at www.casl.gov.
8am – 8:15 Introduction to the panel discussion, Paul Turinsky
8:15-8:45 VERA Core Simulator, Scott Palmtag
9:00-9:30 VERA Neutronics, Scott Palmtag
10:00-10:35 VERA Thermal-Hydraulics & Chemisty, Bob Salko
10:45-11:15 Fuel Performance, Brenden Mervin
11:30-11:50 VERA Uncertainty Quantification and Validation Activities, Paul Turinsky
Between each session the speakers will be available for Q&A
22
ANFM2015 - Advances in Nuclear Fuel Management V
Wednesday, April 1, 2015
Room: Sabal
WM1 Special Session - IAEA Presentation: Beyond 5% Enriched UO2 & ATF Progress.
Chair: Victor Inozemtsev
10:00
Objective of the Special Session is to inform interested participants about the IAEA activities in the area of Fuel Engineering that are relevant to the scope of the ANFM.
Particular attention with be paid and invitation extended to planned Technical Meeting “Beyond 5% enrichment limit for LWR: perspectives and problems” (12-16 October
2015, Vienna) and Coordinated Research Project “Analysis of options and experimental examination of fuels for water-cooled reactors with increased accident tolerance”
(open for proposals, first meeting on 14-18 September 2015).
Room: May
WM2 Management, Design, and Operation Issues of Advanced Reactor Fuels, Practical Design
Constraints, and Advances in On-Line Core Monitoring
Chair: Tomaz Kozlowski
10:00
70
Multiphysics PWR Modeling Including Crud Induced Power Shift (CIPS) and Crud Induced Localized Corrosion (CILC)
Andrew Petrarca, Jeffrey Secker and Michael Krammen
Westinghouse Electric Company, Nuclear Fuel, Hopkins, SC
The goal of the DOE’s Consortium for Advanced Simulation of Light Water Reactors (CASL) is to develop advanced multi-physics methods to improve reactor safety, reduce
waste generation, and enable increased generation of carbon-free nuclear power. CASL is organized to solve problems that challenge operating PWR’s to meet the DOE
goals, such as crud deposits on fuel, grid to rod fretting, fuel assembly distortion, and pelletclad interaction (PCI) that can lead to breaches in PWR fuel cladding. As an initial
step in establishing multi-physics models for PWR crud deposition, the Westinghouse neutronics code ANC and thermal-hydraulics code VIPRE-W were linked with the EPRI
crud and chemistry code BOA3.0 to predict fuel crud deposition. Westinghouse then upgraded the coupled package to make use of EPRI’s latest chemistry code, BOA3.1. A
plant which experienced CIPS during an operating cycle was modeled for this analysis.
10:25
86
I2S-LWR Fuel Management Options for an 18-Month Cycle Length
D. Salazar, F. Franceschini, P. Ferroni (1), B. Petrovic (2)
1) Westinghouse Electric Company LLC, Cranberry Township, PA, USA, 2) Nuclear and Radiological Engineering, Georgia Tech, Atlanta, GA, USA
This paper presents the fuel management options developed for the Integral Inherently Safe LWR (I2S-LWR). The I2S-LWR is a reactor concept of a ~1,000 MWe (2,850
MWt) integral PWR with inherent safety features. The baseline core configuration contains 121 fuel assemblies with a 19×19 square lattice and 144-in active fuel height. The
baseline fuel choice is U3Si2 in advanced FeCrAl-type steel cladding, which is envisioned to enhance accident tolerance but is detrimental to neutron economy. SiC cladding
is also under consideration as it can foster further improvements in accident tolerance with excellent neutron economy. Standard UO2/Zr fuel is under investigation as an
option for accelerated deployment. The performance of these three fuels, U3Si2/FeCrAl, U3Si2/SiC and UO2/Zr, is examined and compared in this paper; the focus is on fuel
management and fuel cycle cost aspects for the I2S-LWR core at the equilibrium cycle with an 18-mo cycle length.
10:50
73
Overview of New MHI Online Core Monitoring System VISION
Yuki Takemoto, Kazuki Kirimura, Naoko Iida, Shinya Kosaka, Hideki Matsumoto
Nuclear Energy System Division, Mitsubishi Heavy Industries, Ltd., Hyogo-ku, Kobe, Hyogo, Japan
Mitsubishi Heavy Industries, Ltd (MHI) has about 20-year experiences of supplying core monitoring systems and their maintenance for Japanese PWR utilities. MHI has
developed a new online core monitoring system (OCMS) VISION. VISION is based on GARDEL-PWR provided by Studsvik Scandpower AB and has been improved to
enhance the user-friendliness with MHI’s PWR core design experiences. Main features of VISION are automated core monitoring, reactivity management, core management
and guidance of operation planning.
Generally, online core simulator is built in a core monitoring system, which performs core calculation periodically to predict 3D power distribution with plant signals. Their
information is displayed with the graphical user interface to support operational management. Usually core simulator installed in an OCMS is not replaced so often, because
replacement of core simulator is not so easy for the customers. However, there would be a need to use different type of simulator, when core designer or fuel vendor is
changed for example. Therefore, the multiple core simulator function has been developed to support easy core simulator replacement in VISION. As a core simulator engine
of VISION, users can alternatively select between MHI’s new 3D core design code COSMO-S and Studsvik Scandpower’s core design code SIMULATE-3 for each cycles
using the multiple core simulator function. Then, this paper describes the VISION’s overview including developed functions.
23
ANFM2015 - Advances in Nuclear Fuel Management V
Wednesday, April 1, 2015
11:15
77
SMR Fuel Cycle Optimization and Control Rod Depletion Using Nestle and LWROPT
Keith E. Ottinger, P. Eric Collins, Nicholas P. Luciano, and G. Ivan Maldonado
The University of Tennessee, Department of Nuclear Engineering, Pasqua Engineering Building, Knoxville, TN
The multi-cycle BWR fuel cycle optimization code BWROPT has been generalized to handle PWRs and SMRs and renamed LWROpt (Light Water Reactor Optimizer) and an
eighth core symmetric shuffle option has also been implemented. The new features of the optimizer are tested using a test case based on an SMR model previously
developed manually. Also, preliminary tests of a spatially-dependent and movable-region isotopic tracking feature under development in NESTLE are illustrated with the
ultimate goal of assessing control rod depletion for very long SMR rodded cycles.
11:40
88
Deterministic Methods for PWR Fuel Loading Optimization
Fariz Abdul Rahman and John C. Lee (1), Fausto Franceschini (2)
1) University of Michigan, Ann Arbor, 2) Westinghouse Electric Company LLC, Cranberry Township, PA, USA
We have developed a multi-control fuel loading optimization code for pressurized water reactors (PWRs) based on deterministic methods. The objective is to flatten the fuel
burnup profile, which maximizes overall energy production. The optimal control problem is formulated using the method of Lagrange multipliers and the direct adjoining
approach for treatment of the inequality power peaking constraint. The optimality conditions are derived for a multi-dimensional multi-group optimal control problem via
calculus of variations. Due to the Hamiltonian having a linear control, our optimal control problem is solved using the gradient method to minimize the Hamiltonian and a
Newton step formulation to obtain the optimal control. We are able to satisfy the power peaking constraint during depletion with the control at beginning of cycle (BOC) by
building the proper burnup path forward in time and utilizing the adjoint burnup to propagate the information back to the BOC. Our test result for the multi-control fuel loading
design is able to achieve the same fuel cycle length as the AP600 first cycle loading with an average reduction of 0.02 wt% 235U enrichment.
24
ANFM 2015 - Advances in Nuclear Fuel Management V
Wednesday, April 1, 2015
CASL VERA Workshop
Room: Palmetto B
Leaders: Dr. Mike
Doster (1), Ms. Rose Montgomery (2)
1) North Carolina State University, 2) Tennessee Valley Authority
Changes to Page 26, CASL VERA Workshop
The Consortium for Advanced Simulation of LWRs (CASL) is developing a suite of tools for high fidelity coupled physics simulations of
currently operating
pressurized
waterDoster
reactors
(PWRs).
This Montgomery
workshop will (2)
provide an introduction to the CASL Virtual Environment for
Leaders:
Dr. Mike
(1),
Ms. Rose
Reactor Applications (VERA). VERA incorporates science-based models, state-of-the-art numerical methods, modern computational sci1) North Carolina State University, 2) Tennessee Valley Authority
ence and engineering practices, and uncertainty quantification tools to provide flexible simulation tools that span the range from atomistic
to engineering scales.
No change to the existing description text.
More information on CASL and VERA are available at www.casl.gov.
Currently,
the agenda
looks like
this:
Participants will explore
the VERA
Core Simulator
and
develop VERA input to run several simple cases. The class size is limited and participants must register in advance. Also, attendance in the CASL technical session is a prerequisite for the workshop. Participants in the
workshop will be required to supply information for approval consistent with U.S. export control requirements, and should bring a laptop
that has the necessary
connect
Pleasesoftware
modify to
it this
way:to an external machine via ssh (e.g., Putty, No Machine) installed.
Time slot 1 – 1:30pm 1:30pm 1:45pm 2:15pm 2:45 BREAK 3pm 3:45pm 4:15pm 4:45pm Topic Introductions, logistics Training Packets Machines & Login Introduction to VERA Common Input Quick Start Tutorial #1 – simple fuel rod cell (2D) Quick Start Tutorial #2 – 17x17 2D lattice (HFP, BOL, mid-­‐plane) Speaker Mike Doster Troy Eckleberry Quick Start Tutorial #3 -­‐ single 3D fuel assembly (includes T-­‐H feedback and depletion) Quick Start Tutorial #4 -­‐ 2D full core using quarter core symmetry (mid-­‐plane, HFP, BOL) Demonstration – 3D full core with feedback and depletion. Closing, Feedback forms, RSA token return Bob Salko 25
Andrew Godfrey Andrew Godfrey Andrew Godfrey Andrew Godfrey Andrew Godfrey Mike Doster ANFM 2015 - Advances in Nuclear Fuel Management V
March 29 - April 1, 2015
Notes
26
PROGRAM AT-A-GLANCE
March 29 - April 1, 2015
SUNDAY
6:00 -9:00 PM
Registration open 3:00 to 5:00 PM @ Palmetto Landing
Welcome Reception - Shore House – Sponsored by Global Nuclear Fuel
MONDAY
Registration open 7:15 - 8:00 AM @ Palmetto Landing
7:00 - 8:00 AM
Breakfast - Palmetto C
Palmetto Ballrooms A & B
8:00 - 9:40 AM
9:40 - 10:00 AM
10:00 AM - 12:05 PM
12:05 - 4:00 PM
4:00 - 4:20 PM
4:20 - 6:00 PM
7:00 -10:00 PM
Opening Plenary Session
Coffee Break – Palmetto Landing – Sponsored by SC Electric & Gas
Sabal
May
MM1 New Modeling Concepts, Reactivity Control,
MM2 Innovative Core Loading, Reload Design, and
Generation of Cross Section Libraries and Whole Core
Licensing
Transport Calculations
Palmetto B
MM3 PANEL Discussion - "Small Modular Reactors:
Challenges and Proposed Solutions to Successful
Deployment"
Chair: Hany Abdel-Khalik
Chair: Andrew Worrall
Chair: Rodolfo Ferrer
Lunch Break
Coffee Break – Palmetto Landing – Sponsored by SC Electric & Gas
ME1 Error Quantification of Core Simulation Capabilities,
ME2 Modeling Methods, Advances in Reactor Stability and
Core Follow Data to Enhance Core Simulation Fidelity,
Fuel Temperature Feedback for Steady-State and
Utilization of Zero Power Physics Tests
Transients
ME3 Advanced or Extended Fuel Cycles and Economic
analysis
Chair: Fausto Franceschini
Chair: Craig Hove
Chair: Vincent Penkrot
Dinner – Shore House – Sponsored by Southern Nuclear Company • Attendance only by purchase of a ticket
TUESDAY
Registration open 7:15 - 8:00 AM @ Palmetto Landing
7:00 - 8:00 AM
Breakfast - Palmetto C
8:00 - 9:40 AM
Sabal
TA1 Core Analysis Tools for Fuel Management: Modeling
and Validation - Part 1
May
TA2 Nodal and Lattice Physics Methods - Part 1
Palmetto B
TA3 Advanced Fuel Management, Multi-dimensional
Burnup Analysis, and Depletion
Chair: Keith Drudy
Chair: Scott Palmtag
Chair: Bojan Petrovic
9:40 - 10:00 AM
10:00 AM - 12:05 PM
12:05 - 4:00 PM
4:00 - 4:20 PM
4:20 - 6:00 PM
7:00 -10:00 PM
Coffee Break – Palmetto Landing – Sponsored by SC Electric & Gas
TM1 Core Analysis Tools for Fuel Management: Modeling
TM2 Nodal and Lattice Physics Methods - Part 2
and Validation - Part 2
TM3 PANEL Discussion - "Adequacy of Methods for Nuclear
Fuel Management”
Chair: Bob StClair
Chair: Jeffrey R. Secker
Chair: Steve Bowman
Lunch Break
Coffee Break – Palmetto Landing – Sponsored by SC Electric & Gas
TE1 Thorium Cycles, MOX utilization, and Plutonium
Disposition
TE3 PANEL Discussion - "Ongoing Fuel Performance and
Fuel Cycle Issues - Driving to Zero"
Chair: Ron Ellis
Chairs: Rob Schneider & Paul Cantonwine
Banquet – Palmetto Ballrooms B & C – Sponsored by Westinghouse • Attendance only by purchase of a ticket
WEDNESDAY
Registration open 7:15 - 8:00 AM @ Palmetto Landing
7:00 - 8:00 AM
Breakfast - Palmetto C
8:00 - 9:40 AM
Sabal
May
WA1 Automated and Interactive Fuel Management Design WA2 Advanced Fuel Assembly and Burnable Absorber
and Optimization Tools - Part 1
Designs
Palmetto B
WA3 PANEL Discussion - "CASL: Consortium for the
Advanced Simulation of Light Water Reactors"
Chair: Gerardo Grandi
Chairs: Paul Turinsky and Rose Montgomery
9:40 - 10:00 AM
10:00 AM - 12:05 PM
Chair: Christian Malm
Coffee Break – Palmetto Landing – Sponsored by SC Electric & Gas
WM1 Special Session - IAEA Presentation: Beyond 5%
WM2 Management, Design, and Operation Issues of
Enriched UO2 & ATF Progress.
Advanced Reactor Fuels, Practical Design Constraints, and
Advances in On-Line Core Monitoring
Chair: Victor Inozemtsev
WA3 continued…
Chair: Tomaz Kozlowski
12:05 PM
Main Conference concluded
12:00 - 1:00 PM
Lunch for workshop attendees only - Edisto
1:00 - 2:45 PM
WORKSHOP: CASL VERA
Attendance restricted to those registered & approved
2:45 - 3:00 PM
Coffee Break
CASL VERA Workshop continued
3:00 - 5:00 PM
5:00:00 PM
Meeting Adjourned