1. CFD MODELING OF SYNGAS COMBUSTION IN GAS TURBINE CONDITIONS
Abdallah Abou-Taouk & Lars-Erik Eriksson
Division of Fluid Dynamics
Department of Applied Mechanics
TURBOPOWER Conference

2. Outline Introduction Kinetic Modeling CFD Modeling
Results & Discussions
Future Work
Publications
Summary

3. Introduction
The number of combustion systems used in the world today is rapidly growing
This induces pollution and environmental problems
Improved combustion technology in terms of efficiency and pollutant emissions important
Development of combustor technology is currently following the general trend towards fuel-flexibility and increased use of bio fuels.
SGT-750
GE-9E…

4. Turbulence –Chemistry Interaction
Introduction
Kinetics
2 & 4-step global schemes methane/air
4-step global scheme syngas
2-step global scheme Selective Non-Catalytic Reduction DeNOx, joint collaboration INSA CORIA France
Turbulence –Chemistry Interaction
EDM
FRC
EDM/FRC
CFD-Modeling
SGT-750 joint collaboration LTH
SGT-100 joint collaboration SIT Sweden & UK
Sandia Flame D

5. Kinetics – M4 scheme for Methane-Air mixture
Laminar flame speed model in CHEMKIN coupled to the modeFRONTIER
Lean optimization for 16 variables at Pin=1bar, Tin=295K-650K simultaneously
Freezing the obtained scheme and optimize the correction function at rich conditions
Optimizing the pressure correction factor for Pin=1-6 bar

6. Kinetics – M4 scheme for Methane-Air mixture

7. Kinetics – M4 scheme for Methane-Air mixture
Good agreement for laminar flame speed, major species and adiabatic flame temperatures at different equivalence ratios and pressures

8. Global Mechanism - Syngas mixture (CH4+CO+H2)
CH O2 CO + 2H2
H O H2O
CO O CO2
CO + H2O CO2 + H2
Good agreement for laminar flame speed, major species and adiabatic flame temperatures at different equivalence ratios at atmospheric pressure

9. 2-step global scheme Selective Non-Catalytic Reduction DeNOx
Optimizing a 2-step (OPT_2S) global scheme with the detailed NNH mechanism (207 reactions)
Defining the mixing fraction Z
Optimization is done for the interval
Z: 0 – 0.1
T: 1100K – 1400K
Using the modeFRONTIER as the optimization tool together with the CHEMKIN software, the isothermal homogenous reactor
A INLET
Z=0
Y_O2_A 0,
Y_H2O_A 0,
Y_N2_A 0,
Y_NO_A 0,
Y_CO2_A 0,
S_Y_A 1
B INLET
Z=1
Y_H2O_B
0,75
Y_NH3_B
0,25
S_Y_B

10. Results 2-step scheme vs. Detailed NNH (207 reactions)
Figure showing the detailed NNH mechanism compared to the OPT_2S scheme at different temperatures and Z values, τ = 0.5 [s]
Figure showing comparison between the detailed NNH mechanism, the reduced SNCR scheme and the OPT_2S scheme at Z=0.048, τ = 0.5 [s]

11. CFD Results of SGT-750
SGT-750 is an industrial gas turbine designed and manufactured at SIT, Finspång
Power output 37 MW

12. CFD – Meshing Code : ICEMCFD 12.1 - Hexahedral mesh - 9.5-18 M cells
High-Quality grid

13. CFD Modeling Methane-Air Mixture PIV data
Emissions data: averaged at plane 7

14. Methane oxidation & OH radical
Averaged transient reaction rate for methane oxidation using the SAS-SST model. Red: highest reaction rate, blue: lowest reaction rate
Instantaneous plots from OH-PLIF measurements showing the OH radical at six different times.
Averaged plot from the OH-PLIF measurements showing the OH radical.

15. CFD Results of SGT-100
SGT-100 is an industrial gas turbine designed and manufactured at SIT Ltd, UK
Power output ranging from to 5.7 MW

16. Geometry– Meshing Code : ICEMCFD 12.1 - Hexahedral mesh - 8.2 M cells
High-Quality grid

17. Evaluation planes
Measurements locations
6 points
4 PIV planes

18. Normalized Axial Velocity, Non-reacting flow CASE B

19. Normalized Radial Velocity, Non-reacting flow CASE B

20. Contour plots LES, Non-reacting flow CASE B
Averaged Pressure
Averaged Axial Velocity
Snapshot Pressure
Snapshot Axial Velocity

21. Normalized Velocity, reacting flow CASE A
PIV plane PIV plane 2 PIV plane PIV plane 4

22. Temperature, reacting flow CASE A

23. CFD animation Contour of Temperature
Iso-surface of highest Reaction rate
Contour of CO Mass Fraction
LES simulation with the new 4-step scheme for methane-air, introduction of F factor in all reaction steps

24. Future Work Finalize work from the visiting time in INSA/ROUEN.
Writing a joint journal article regarding the chemistry optimization and a journal article regarding the LES modeling.
Finalize CFD simulation for the SGT-100 configuration, write a joint journal paper together with SIT Finspång and UK
Writing Ph.D thesis autumn 2013
Defend spring 2014

25. Diploma Works Master Thesis
40 weeks: A. Khodabandeh, “CFD Modelling of Generic Gas Turbine Combustor”, Department of Applied Mechanics, Division of Fluid Dynamics, Chalmers University, Sweden,
20 weeks: S. M. Mohseni, “Optimization of Global Reaction Mechanisms Evaluated on The Sandia Flame D, Department of Mechanical Engineering, Blekinge Institute of Technology, Karlskrona, Sweden, 2012.

26. Publications Lic. Thesis presented Nov 2011.
A. Abou-Taouk and L.E Eriksson, “Optimized Global Mechanisms For CFD Analysis Of Swirl- Stabilized Syngas Burner For Gas Turbines”, ASME Turbo Power Expo, Power for land, Sea and Air, GT , Vancouver, Canada, 2011.
A.Abou-Taouk, R. Whiddon, I. R. Sigfrid and L.E. Eriksson, 2011, “CFD Investigation Of Swirl- Stabilized Flexi-Fuel Burner Using Methane-Air Mixture For Gas Turbines”, 20th International Society for Airbreathing Engines, ISABE , Gothenburg, Sweden.
A. Abou-Taouk and L.E. Eriksson, “Evaluation of Optimized 3-step Global Reaction Mechanism for CFD Simulations on Sandia Flame D”, The 6th Symposium on Numerical Analysis of Fluid Flow and Heat Transfer, ICNAAM , Halkidiki, Greece, 2011.
A.Abou-Taouk, R. Whiddon, I. R. Sigfrid and L.E. Eriksson, ”A Four-Step Global Reaction Mechanism for CFD Simulations of Flexi-Fuel Burner for Gas Turbines”, 7th International Symposium on Turbulence, Heat and Mass Transfer, Palermo, Italy, 2012.
I .R. Sigrid, R. Whiddon, A. Abou-Taouk, R. Collin, and J. Klingmann, “Experimental Investigations of an Industrial Lean Premixed Gas Turbine Combustor With High Swirling Flow”, ASME Gas Turbine India Conference, GTIndia , Mumbai, India, 2012.
A.Abou-Taouk, S. Sadasivuni, D. Lörstad and L.E. Eriksson, ”Evaluation of Global Mechanisms for LES Analysis of SGT-100 DLE Combustion System”, ASME Turbo Power Expo, Power for land, Sea and Air, GT , San Antonio, Texas, USA, 2013.
B. Farcy, A.Abou-Taouk, L. Vervisch, P. Domingo, N. Perret ”Numerical Modeling of Selective Non Catalytic Reduction DeNOx Process”, 7th European Combustion Meeting, Lund, Sweden, June
Lic. Thesis presented Nov 2011.

27. Summary Thank you for your attention
A promising optimization methodology has been developed: 2-4 step global schemes have been optimized for methane-air, syngas and Selective Non-Catalytic Reduction DeNOx
Successful validation of the CFD model compared to a prototype burner of the SGT-750 engine and the SGT- 100 burner in terms of temperature, emission and velocity data
Thank you for your attention