1. No category

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Copyright 0 1997 by ASME
DEVELOPMENT OF A DRY LOW EMISSION COMBUSTOR
FOR THE ASE1 20 INDUSTRIAL GAS TURBINE ENGINE I
. Printed in U.S.A
III 111 1 MAW 111 111
P. Samuel and J.E. Lenertz
AlliedSignal Engines
Box 52181, Phoenix, AZ 85072-2181
D.B. Bain
CFD Research Corporation
Huntsville, AL 35805
Mowill
Optimal Radial Turbines B.V.
7550 AV Hengelo, The Netherlands
ABSTRACT
OPFtA
Pat.
pp.
RQL
sec
TBC
U.S.
USA
UHC
U.K.
Vol.
vppm
2-D
3-D
The development of a dry, low-emissions combustor for the
AlliedSignal Model ASE120 industrial gas turbine engine is in
progress. The combustor is designed to provide IOMW of engine
power output and also meet all current exhaust emissions
requirements. The combustion system has a single-stage premixer
and a novel, yet simple, variable geometry to control the flame
temperature over the entire operating range of the ASE120 gas
turbine engine. Design concepts of this lean premix-prevaporize
combustor operating on air staging technology are presented.
Preliminary results from computational fluid dynamics (CFD)
analyses of the system are discussed.
NOMENCLATURE
AIAA
American Institute of Aeronautics and Astronautics
ASME American Society of Mechanical Engineers
CFD
Computational Fluid Dynamics
Carbon Monoxide
CO
DF-2
Diesel Fuel, Grade No. 2
HPC
High Pressure Compressor
Hr
High Pressure Turbine
hr
Hours
ID
Inside Diameter
ISA
International Standard Atmosphere
Kelvin
Kilograms
kg
kW
KiloWatts
LPC
Low Pressure Compressor
LPP
Lean, Premix, Prevaporize
Low Pressure Turbine
LPT
MW MegaWans
No.
Number
NOx
Nitrogen Oxides
OD
Outside Diameter
Ohio
OH
1
Optimal Radial Turbines, BY. (The Netherlands)
Patent
Pages
Rich Burn, Quick Quench, Lean Burn
Second
Thermal Bather Coating
United States
United States of America
Unburned HydroCarbons
United Kingdom
Volume
Parts Per Million by Volume
Two-Dimensional
Three-Dimensional
INTRODUCTION
AlliedSignal Aerospace (USA), Optimal Radial Turbines B.V.
(The Netherlands), Aerospace Industrial Development Corporation
(Republic of Taiwan), Mitsubishi Heavy Industries (Japan) and
Hyundai Space and Aircraft (Republic of Korea) are working
together to develop a IOMW-class thy, low-emissions gas turbine
engine for industrial applications. The gas producer section of the
new engine design (designated as Model ASEI20), is derived from
the production AlliedSignal Model TFE1042-70 low-bypass-ratio,
afterbuming turbofan engine, with a Mitsubishi Heavy Industries
free-shaft power turbine. The ASE120 engine is designed for use in
power generation applications involving synchronous operation, or
shaft-power applications such as gas compression and marine
propulsion.
To meet or exceed the increasingly stringent worldwide exhaust
emissions requirements, the ASEI20 engine will be fitted with dry,
low-emissions combustors with dual-fuel capability. The combustor
design is based on patented, dry low-emissions technology from
Optimal Radial Turbine B.V. (The Netherlands).
Presented at the Intexnational Gas Turbine & Anoengine Congress & Fodadtion
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on 12/29/2014
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of Use:
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Orlando, Florida
June
2—June
5,1997
—
This paper focuses on various aspects of the ASE120 combustor
design and development process and preliminary results obtained
from computational fluid dynamics (CFD) analyses.
Figure 1 compares cross-sections of the ASE120 industrial engine
(top half of figure) and the 17E1042 aero engine (bottom half). The
ASEI20 industrial engine is arranged into four primary modules: the
high-pressure compressor (HPC), low-pressure compressor (LPC),
low-emissions combustor, and free-shaft power turbine.
BACKGROUND
The new Model ASE120 industrial turbine engine design is based
principally on the production Model 1FE1042, which is a lowbypass-ratio, afterbuming turbofan engine designed for supersonic
military aircraft propulsion. The TFE1042 consists of a three-stage,
axial-flow low-pressure compressor (LPC); a four-stage axial-flow
and single-stage centrifugal-flow high-pressure compressor (HPC);
an annular combustion system; a single-stage, axial high-pressure
turbine (HPT); a single-stage, axial low-pressure turbine (LPT); and
the (optional) afterburner. The TFE1042 aero engine has on overall
pressure ratio of 19 and a bypass ratio of 0.4, and operates at a
turbine inlet temperature of 1617K (1343C).
The Model ASE120 industrial engine was derived by replacing the
thrust-producing fan stage of the aero engine with three axial-flow
compressor stages, and the aero combustor with a dry, low-emissions
combustor. The gas-producing section of the ASE120 engine is
aerodynamically coupled with a Mitsubishi free-shaft power turbine,
since the outlet total pressure from the low-pressure turbine is about
3.7 times atmospheric pressure. The power turbine extracts work
from the hot gases leaving the low-pressure turbine while expanding
the gases to atmospheric pressure.
Thermodynamic cycle studies have calculated the following
characteristics for the resulting ASEI 20 engine operating on natural
gas fuel at sea level, ISA conditions:
Parameter
DRY LOW-EMISSIONS COMBUSTOR
The basic requirements for the design of the dry, low-emissions
combustor for the ASE120 engine are as follows:
• Provide 10 MW power output at sea level, ISA day conditions
• Operate on natural gas or other liquid fuel(s), such as DF-2 diesel
fuel
• Meet or exceed all current (worldwide) exhaust emissions
requirements. The emissions design target for natural gas operation
is to produce less than 10 vol. parts per million (vppm) of nitrogen
oxides (N0x), carbon monoxide (CO), and unburned hydrocarbons
(UHC); for DF-2 diesel fuel, less than 25 vppm of NOx, less than
50 vppm CO, and less than 25 vppm UHC.
• Provide reliable service with regard to ignition, durability, and
operability. The combustor liner is designed to provide 90,000 hrs.
of service with refurbishment after 30,000 hrs.; the combustor case
is designed for a life requirement of 180,000 hrs. operation.
Combustor Design Concept
The design of stationary gas turbine combustors has become
increasingly challenging, due to ever more stringent emissions
regulations, customer requirements for engine operation on a variety
of fuels, and higher reliability and operability goals. Traditional
combustor designs typically took advantage of a primary zone
operating at relatively high temperature to provide adequate flame
stability and combustion efficiency, at the expense of high NO
emissions. Until recently, methods such as water or steam injection,
as well as exhaust gas processing such as selective catalytic
reduction, have been used extensively in stationary gas turbine
engines to meet the emissions regulations. Owing to high operating
and installation costs, reduced engine reliability, and other
disadvantages associated with these older methods, more recently
industrial gas turbine engine manufacturers in general have adopted
other dry control methods, such as lean-premix-prevaporization
Estimated Value
Power output
10MW
Thermal Efficiency
Turbine Inlet Temperature
35 Percent
1585K (131 IC)
Overall Pressure Ratio
Inlet air flow rate
21
32 kg/sec
Exhaust Temperature
790K (516C)
Mitsubishi
Power Turbine
Combustor
Turbine
compressor
ASE120
41111111 iii iirmja4i
■-- arei‘eilthipa
•
1111 1
't t ■
1",=-•
Ski
(Afterburner Not Shown)
TFE1042
Oor
-r
07080- 1 A
Figure 1. ASE120 Industrial Turbine Engine (Top Half) Is Derived From TFE1042 Aero Propulsion Engine (Bottom Half).
2
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Cast Ribs
(Turbulators)
G7080-6
Figure 6. Cross-Section of the Combustor Liner.
Figure 7. Combustor Case and Valves Assembly
(One Valve Shown).
As shown in Figure 4, the excess air that is bypassed by the threeway valve is allowed to enter a bypass manifold and then into 24
discrete bypass tubes placed at the exit of the combustor. These
bypass tubes are sized to allow maximum bypass flow, occurring at
the engine idle power condition. The bypass tubes, cast as part of the
liner, will butt up against the case with a seal to minimize leakage.
The dilution orifices will be cast in the liner on both the inside and
outside diameter (ID and OD) walls. The dilution orifices on the OD
side are located just upstream of the bypass tubes. The cast material
yields excellent long-term creep rupture properties for the required
operational life.
As discussed in the previous section, the design of the premixing
system is of paramount importance to the success of attaining low
NO emissions levels. The present system uses a venturi to premix
the fuel and air entering the combustor. The air that is diverted to the
combustor by the three-way valve enters the venturi through a
perforated cone.
Fuel is injected into the venturi from a dual-fuel piloted airblast
atomizer that can be used with either natural gas or diesel (DF-2)
fuel. The airblast air is bled from the compressor exit to maximize
the available pressure drop for best fuel atomization. The venturi
injects the fuel/air mixture into the combustor with a clockwise swirl
(aft looking forward). The venturis provide high-velocity smooth
passages for mixing and vaporizing, but with a short residence time
to prevent autoignition with diesel fuel at elevated pressures and
temperatures, as well as preventing flashback burning in the tube.
Figure 7 provides an overview of the combustor case and valve
assembly. The three-way valves are located outside the combustor
case in two locations (only one is shown in the figure); these valves
schedule the flow to the bypass ducts as well as the venturis that
premix the fuel and air for the combustor. The valve/case assembly
consists of the bypass duct that supplies air to the bypass tubes and
the venturi ducts that supply air to the venturis.
Although the main part of the combustor liner is cooled using
convective techniques, effusion cooling will be used at the combustor
exit to keep the wall temperatures at the desired level to provide
required life. In addition, two local patches of effusion cooling will
be used to cool the wake regions behind the venturis, where backside cooling is disrupted. The effusion cooling also helps develop
the required radial temperature profile at the combustor exit.
COMPUTATIONAL MODEL
Computational fluid dynamics (CFD) analyses of the ASE120
annular combustor design were performed using the commercially
available CFD Research Corporation computer code CFD-ACE.
This code has the capability to analyze turbulent reacting flows, and
has been thoroughly validated against benchmark test data. The CFD
modeling of the ASE120 combustor involved the solution of mass,
momentum, and energy equations within the computational domain.
Turbulence was accounted by the use of a k-e model. The reaction
rate was calculated using a kinetic model with a two-variable,
prescribed PDF formulation. The models that were analyzed using
CFD techniques included: combustor internal flow involving lean
premixed combustion; combustor external flow around the liner and
simulation of dilution/bypass flow at the combustor exit; a conjugate
heat transfer analysis to predict liner temperatures; and simulation of
fuel-air mixing within the premixer. All multi-block, structured grids
were generated using the CFD-GEOM code, and the results were
viewed and processed using the CFD-VIEW and CFD-POST codes.
RESULTS AND DISCUSSION
Figure 8 shows the computational domain used for the combustor
internal flow analysis. Only a 180-degree sector was modeled,
because of the symmetry of the combustor. The number of active
grid nodes within the model was about 125,000.
5
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Liner wall heat transfer is enhanced by the use of small cast ribs
(turbulators), as shown in Figure 6. A shroud is used on the outside
diameter (OD) to help maintain the required flow velocity to cool the
liner. A thermal barrier coating (TBC) is also applied to the inside of
the liner.
The OPRA combustor design utilizes an electrically-actuated air
modulating valve to divide the engine airflow between the
combustion air and the dilution air; the dilution air bypasses the
combustion zone and mixes into the combustion gas upstream of the
nozzle guide' vane through dilution holes. The air modulating valve
and the fuel metering valve provide full control of the fuel-air ratio,
which in turn determines the flame temperature. Together with a
well-developed mixing system, in which the fuel is fully vaporized
and premixed with air before entering the combustion chamber,
extremely low emissions levels are obtained. Recently, OPRA has
demonstrated this concept in the Model OP-16 gas turbine engine, a
single-shaft, radial engine with a power generation capacity of
1600kW.
Combustor Design Description
The OPRA air-staging concept has been applied to the ASE120
combustor design. Application of this variable-area geometry
concept is shown schematically in Figure 3. At any power condition,
all of the combustion air flows into the burner through two
premixers, and the remaining air flows through dilution and bypass
orifices located at the exit of the burner and upstream of the turbine
stator vanes. The dilution orifices are sized for maximum power,
whereas the bypass orifices are sized for idle power. The air flowing
into the combustor is controlled with the help of two three-way
valves, as shown in Figure 3.
G7080-4
Figure 4. Cross-Section of ASE120 Combustor.
Combustor Bypass Flow
HPC
3-Way
Valve
HPT
G7080-3
Figure 3. ASE120 Combustor Airflow Schematic.
At maximum power, all of the combustion air passes through the
burner, and the remaining excess air flows through the dilution
orifices. At lower power, only the air required to maintain a desired
constant flame temperature is allowed into the combustor, and the
remaining air is bypassed through combustor bypass and dilution
orifices located near the combustor exit. This design concept will
allow the pressure drop across the combustor to remain constant at all
power levels.
Figures 4 and 5 show cross-sectional views of the combustion
system. The airflow into the combustion section will be deswirled to
zero degrees at the compressor exit and diffused to a low Mach
• number by extending the radial diffuser. This minimizes the
combustor pressure drop, while providing high-velocity cooling air
around the externally-cooled, annular combustor liner. Unlike film
cooling, convective cooling of the liner prevents any quenching of
CO and UHC reactions.
G7080-5
Figure 5. Cross-Section of the Combustor, Showing
the Venturi and the Valve Assembly.
4
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Cast Ribs
(Turbulators)
G7080-6
Figure 6. Cross-Section of the Combustor Liner.
Figure 7. Combustor Case and Valves Assembly
(One Valve Shown).
As shown in Figure 4, the excess air that is bypassed by the threeway valve is allowed to enter a bypass manifold and then into 24
discrete bypass tubes placed at the exit of the combustor. These
bypass tubes are sized to allow maximum bypass flow, occurring at
the engine idle power condition. The bypass tubes, cast as part of the
liner, will butt up against the case with a seal to minimize leakage.
The dilution orifices will be cast in the liner on both the inside and
outside diameter (ID and OD) walls. The dilution orifices on the OD
side are located just upstream of the bypass tubes. The cast material
yields excellent long-term creep rupture properties for the required
operational life.
As discussed in the previous section, the design of the premixing
system is of paramount importance to the success of attaining low
NO emissions levels. The present system uses a venturi to premix
the fuel and air entering the combustor. The air that is diverted to the
combustor by the three-way valve enters the venturi through a
perforated cone.
Fuel is injected into the venturi from a dual-fuel piloted airblast
atomizer that can be used with either natural gas or diesel (DF-2)
fuel. The airblast air is bled from the compressor exit to maximize
the available pressure drop for best fuel atomization. The venturi
injects the fuel/air mixture into the combustor with a clockwise swirl
(aft looking forward). The venturis provide high-velocity smooth
passages for mixing and vaporizing, but with a short residence time
to prevent autoignition with diesel fuel at elevated pressures and
temperatures, as well as preventing flashback burning in the tube.
Figure 7 provides an overview of the combustor case and valve
assembly. The three-way valves are located outside the combustor
case in two locations (only one is shown in the figure); these valves
schedule the flow to the bypass ducts as well as the venturis that
premix the fuel and air for the combustor. The valve/case assembly
consists of the bypass duct that supplies air to the bypass tubes and
the venturi ducts that supply air to the venturis.
Although the main part of the combustor liner is cooled using
convective techniques, effusion cooling will be used at the combustor
exit to keep the wall temperatures at the desired level to provide
required life. In addition, two local patches of effusion cooling will
be used to cool the wake regions behind the venturis, where backside cooling is disrupted. The effusion cooling also helps develop
the required radial temperature profile at the combustor exit.
COMPUTATIONAL MODEL
Computational fluid dynamics (CFD) analyses of the ASE120
annular combustor design were performed using the commercially
available CFD Research Corporation computer code CFD-ACE.
This code has the capability to analyze turbulent reacting flows, and
has been thoroughly validated against benchmark test data. The CFD
modeling of the ASE120 combustor involved the solution of mass,
momentum, and energy equations within the computational domain.
Turbulence was accounted by the use of a k-e model. The reaction
rate was calculated using a kinetic model with a two-variable,
prescribed PDF formulation. The models that were analyzed using
CFD techniques included: combustor internal flow involving lean
premixed combustion; combustor external flow around the liner and
simulation of dilution/bypass flow at the combustor exit; a conjugate
heat transfer analysis to predict liner temperatures; and simulation of
fuel-air mixing within the premixer. All multi-block, structured grids
were generated using the CFD-GEOM code, and the results were
viewed and processed using the CFD-VIEW and CFD-POST codes.
RESULTS AND DISCUSSION
Figure 8 shows the computational domain used for the combustor
internal flow analysis. Only a 180-degree sector was modeled,
because of the symmetry of the combustor. The number of active
grid nodes within the model was about 125,000.
5
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A perfectly-mixed fuel-air mixture burning at less than 1900K is
expected to produce less than 10 vppm NOx (Steele ez al, 1996;
Leonard and Stegmaier, 1993; Sattlemayer et al., 1990). The actual
values of combustor operational flame temperature will be
determined from planned future rig tests, which are discussed in a
later section.
Figure 10 shows the fluid flow field entering the combustion
chamber from the venturi. The predicted swirl values at the
combustor exit are 51 degrees at maximum power, and 40 degrees at
idle power, in the absence of any dilution flow. This level of swirl at
maximum power conditions is not acceptable to the turbine stator
inlet, since the existing stator vanes from the aero engine were
designed for zero-degree inlet swirl angle. It will be shown later that
by properly feeding the dilution flow at the combustor exit, the exit
swirl angle can be reduced to an acceptable level.
Figure 8. Computational Grid For Combustor
Internal Flow Simulation.
The calculation domain started at the throat of the premix tube
and extended to the combustor exit. The premix tube throat inlet
conditions were extracted from a detailed two-dimensional (2-D)
axisymmeuic premixer model analysis. The dilution/bypass flows
were not modeled in this analysis, since the model was only intended
to provide the characteristics of the combustor internal aerodynamics,
and the computational expense of modeling the large number of
dilution holes and bypass tubes would have been excessive.
• Figure 9 shows the predicted combustor temperature levels at
engine maximum power conditions on an axial slice through the
prernixer centerline. This prediction example shows that the flame is
located downstream of the premixer, and that the temperature is fairly
uniform at approximately 1900K within the combustor.
Figure 10. Vector Plot of Predicted Combustor Internal
Flow At Maximum Power Operating Condition.
Figure 9. Predicted Temperatures Within the Combustor
At Maximum Power Operating Condition.
The premixer was modeled using CFD to determine the level of
fuel-air premixing, the susceptibility of flow separation in the
diffusing passage, and the possibility of flashback into the premix
tube. The calculation domain extended from the exit of the fuel
nozzle swirl vanes to a "dump can" combustor. Figure 11 depicts the
temperature levels within and downstream of the premixer. Neither
flashback nor flow separation was predicted to be a problem at any
engine power setting.
At high power, 90 percent of the premixer airflow enters through
the premixer screen, and the remaining air enters through the fuel
nozzle. The fuel/air mixture discharged by the fuel nozzle mixes
with the air flowing through the screen. The level of mixing
produced within the venturi for a baseline configuration is shown in
Figure 12. Although the turbulence enhancement from the screen
helps the mixing process, it still requires further improvement.
Producing very low levels of NO x emissions requires a homogeneous
fuel/air mixture at the exit of the premixer section. We are currently
analyzing several other configurations in an attempt to improve the
mixing process. However, the accuracy of the CFD analysis in
predicting the mixing levels is not well established. Therefore, rig
tests are also planned to examine the mixing performance, and hence
optimize the premixing section.
6
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Figure 11. Reacting Flow Simulation Through Premixer (Shown as Temperature Contours in Degrees K).
Figure 12. Predicted Mixing Within the Premixer (Shown as Contour Plots of Equivalence Ratio Values).
Outer
Annulus
The dilution zone at the exit of the combustor was modeled to
determine the exit swirl angle, temperature pattern factor, and radial
profile. The analysis was carried out for maximum power and idle
power conditions. The flow conditions inside the combustor were
specified using the outputs from the combustor internal flow
modeling.
To
Vaporizer
Tube
Compressor
Discharge
Only a single bypass tube, as well as a single dilution orifice on
the ID and OD, were modeled, instead of the ISO-degree sector that
was modeled for the internal flow simulations. This allowed the
orifices to be properly resolved, and still reduced the total number of
grid points required. The complete external passages around the
combustor were modeled, starting at the compressor deswirl vanes.
Figure 13 shows the details of the geometry analyzed.
Internal
Combustor
Flow
Bypass
AIrTube
Dilution
Orifices
As shown in Figure 14, the predicted maximum combustor exit
swirl angles are 41 and 15 degrees, for the maximum and idle power
conditions, respectively. Three-dimensional (3-D) viscous flow
analysis of the existing turbine stator vanes indicates no penalty on
performance at this level of swirl angle. However, the vane Cooling
flows will have to be redistributed to optimize the stator cooling.
Gme0-13
Bypass
Air
ToTurbine
Cooling
To'Rabin°
Cooling
Inner
Annulus
Figure 13. ASE120 Combustor Dilution/Bypass
Flow Configuration.
7
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A conjugate heat transfer analysis to predict the liner
temperatures was performed, incorporating the combustor interior
and external flow fields. The preliminary analysis results indicated
acceptable wall temperatures everywhere, except for certain locations
at the combustor exit near the dilution zone, and the wake behind the
premix tube, where backside cooling is disrupted. Subsequently,
effusion cooling was added to these areas. Since the combustion
reactions will be complete near the combustor exit, the addition of
effusion cooling at this location is not expected to increase the CO
levels. Also, since the amount of effusion cooling at the wake of the
premixer is only a very small fraction of the combustor flow, it
should not create any major wall quenching effects in these two small
areas.
0
-5 -10co
S -15—
▪
m
ow -20-
O Maximum Power
• Idle Power
0
B, -25— 0
4
• • • mm mm m
mmmm m
-30 —
O
0, -35 —
0
-40 —
-45
0 00
O 0 000 0
0 0 °
ill
III
III
I
10 20 30 40 SO 60 70 60 90 100
Span, Percent
07080-14A
COMBUSTOR DESIGN VAUDATION PLANS
Rig tests, followed by full engine tests of the combustor, are
planned to validate the combustor design during development. A
high-pressure pipe rig test will be carried out, to evaluate the mixing
quality within the premixer section using gaseous as well as liquid
fuels. Tests are also underway to evaluate autoignition and flame
flashback conditions for the premixer section. Furthermore, a fullannular test rig will be used to assess the combustor performance,
including flame stability, combustor dynamics, emissions, durability,
and fuel switching between gas and distillate fuels. Also, the
operation of the air valves, flame temperature sensor, and associated
control hardware will be tested simultaneously in the rig. The
culminating test will be a full engine test, during which the
combustor performance will be measured.
Figure 14. Predicted Combustor Exit Swirl Angles For
Maximum and Idle Power Operating Conditions.
Figure 15 shows the predicted temperature profiles as a function
of channel height. The predicted pattern factors at maximum and idle
power are 0.09 and 0.16, respectively. It is interesting to note that for
the maximum power condition, the radial temperature peaks at 50percent span; whereas at idle power conditions, the temperature is
lowest at about 50-percent span. This is due to the fact that at idle
power a large amount of cold air flows through the bypass tubes and
penetrates into the mid-section of the flow.
CONCLUSIONS
60 —
A dry, low-emissions gas turbine combustor utilizing LPP
technology is currently under development for the new AlliedSignal
Model ASE120 industrial gas turbine engine. The ASE120
combustor design uses a patented, single-stage premixer and a
simple, variable-geometry concept to control the flame temperature
over the entire operating range of the engine. This novel design
provides flexibility of operation while maintaining low exhaust
emissions at all engine power levels. Preliminary results from CFD
analyses indicate promising results for the combustor internal
aerodynamics and exit flow conditions. The CFD analysis results
were incorporated into the final design of the ASE120 combustor
details. Rig tests are underway to validate the design and the CFD
predictions.
O Maximum Power
• Idle Power
50 —
40 —
30 —
be 20 —
ce
10 —
-10 —
g -20-30 —
-40 —
-SO —
-60
0
G7080-15A
1
1
1
10
20
30
1
1
I
40
50
60
Span, Percent
1
1
1
1
70
80
90
100
ACKNOWLEDGMENTS
The authors wish to thank AlliedSignal Engines management for
permission to publish this paper. The authors wish to acknowledge
the contributions of the ASE120 design team to the work described in
this paper. The contributions of many colleagues in gathering the
information and preparing this manuscript are appreciated.
Figure 15. Predicted Radial Temperature Profiles.
8
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and 5,481,866.
Correa, M.S., 1992, "A Review of NOx Formation Under Gas
Turbine Combustion", Combustion Science and Technology Vol.
87, pp. 329-362.
Myers, G.A., Jackson, A.J.B., 1994, "Development of the Trent
Econopac", ASME 94-GT-446, presented at the Gas Turbine and
Aeroengine Congress & Exposition, The Hague, Netherlands.
Davis, L.B., 1996. "Dry Low NOX Combustion Systems for GE
Heavy-Duty Gas Turbines", ASME 96-GT-27, presented at the
International Gas Turbine and Aeroengine Congress & Exhibition,
Birmingham, U.K.
Puri, R., Stansel, D.M., Smith, D.A., and Razdan, M.K., 1995,
"Dry Ultra-Low NOx 'Green Thumb' Combustor for Allison's 501-K
Series Industrial Engines", ASME 95-GT-406, presented at the Gas
Turbine and Aeroengine Congress & Exposition, Houston, USA.
Dobbeling, K., Eroglu, A., Winkler, D., and Sattelmayer, T.,
1996, "Low NO Premixed Combustion of MBtu Fuels in a Research
Burner", ASME 96-GT-125, presented at the International Gas
Turbine and Aeroengine Congress & Exhibition, Birmingham, U.K.
Razdan, M.K., McLeroy, J.T., and Weaveer, Wt., 1994,
"Retrofittable Dry Low Emissions Combustor for 501-7 Industrial
Gas Turbine Engine", ASME 94-GT-439, presented at the Gas
Turbine and Aeroengine Congress, Hague, The Netherlands.
Fiorentino, Al, Greene, W., Kim, J.C., and Mularz, E.J., 1980,
"Lean, Premixed Prevaporized Fuel Combustor Conceptual Design
Study", ASME 80-GT-16.
Fric, TS., 1992, "Effects of Fuel-Air Unmixedness on NOx
Emissions, A1AA 92-3345.
Rawlins, D.C., 1995, "Dry Low Emissions: Improvements to the
SoLoN0x Combustion System" Proceedings of the Canadian Gas
Association 11th Annual Symposium on Industrial Applications of
Gas Turbines, Banff, Alberta, Canada.
Hayashi, S., Yamada, H., and Shimodaira, K., 1996, "Engine
Testing of a Natural Gas-Fired, Low-N0x, Variable Geometry Gas
Turbine for a Small Gas Turbine", ASME 96-GT-465, presented at
the International Gas Turbine and Aeroengine Congress &
Exhibition, Birmingham, U.K.
Satdemayer, T., Felchlin, M.P., Naumann, J., Heller, J., and
Styner, D., 1990, "Second-Generation Combustors for ABB Gas
Turbines: Bumer Development and Tests at Atmospheric Pressure".
ASME 90-GT-162, Presented at the Gas Turbine and Aeroengine
Congress, Brussels, Belgium.
Nasal, J., Watanabe, T., and Toh, H., 1996, "Development of a
Dry Low NOx Combustor for 2MW Class Turbine", ASME 96-GT53, presented at the International Gas Turbine and Aeroengine
Congress & Exhibition, Birmingham, U.K.
Schlein, B., 1995, "Dry Low Emission in the G08-2",
Proceedings of the Canadian Gas Association 1 I th Annual
Symposium on Industrial Applications of Gas Turbines, Banff,
Alberta, Canada.
Leonard, G., and Stegmaier, J., 1993, "Development of an
Aeroderivative Gas 'Turbine Dry Low Emissions Combustion
System", ASME 93-GT-288, presented at the Gas Turbine and
Aeroengine Congress, Cincinnati, OH.
Steele, B.C., Tonouchi,
Nicol, D.G., Horning, D.C., Mahe,
P.C., and Pratt, D.T., 1996, "Characterization of NOx, N 20, and CO
for Lean-Premixed Combustion in a High-Pressure Jet Stirred
Reactor", ASME 96-CT-I28, presented at the International Gas
Turbine and Aeroengine Congress & Exhibition, Birmingham, U.K.
Maughan, JR., Warren, R.E., and Tolpadi.. A.K., 1992, "Effect
of Initial Fuel Distribution and Subsequent Mixing on Emission from
Lean Premixed Flames", ASME 92-GT-121.
Willis, D.J., Toon, 1.I., Schweiger, T. and Owen, D .A., 1993,
"Industrial RB211 Dry Low Emission combustion", ASME 93-GT391, presented at the Gas Turbine and Aeroengine Congress,
Cincinnati, USA
Mowill, R.J., 1992, "Low Emissions Gas Turbine Combustor",
U.S. Pat. No. 5,156,002.
White, DJ., Roberts, P.B., and Compton, W.A., 1973, "Low
Emission Variable Area Combustor for Vehicular Gas Turbines,
ASME 73-GT-I9.
Mowill, R.J., 1995, "Single Stage Premixed Constant Fuel/Air
Ratio Combustor", U.S. Pat. No. 5,477,671.
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