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 2012-04-24

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

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…

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

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

Kinetics – M4 scheme for Methane-Air mixture        

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

Global Mechanism - Syngas mixture (CH4+CO+H2) CH4 + 0.5 O2 CO + 2H2 H2 + 0.5 O2 H2O CO + 0.5 O2 CO2 CO + H2O CO2 + H2 Good agreement for laminar flame speed, major species and adiabatic flame temperatures at different equivalence ratios at atmospheric pressure

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 0,09388415 Y_H2O_A 0,22967024 Y_N2_A 0,57623614 Y_NO_A 0,00134204 Y_CO2_A 0,09886742 S_Y_A 1 B INLET Z=1 Y_H2O_B 0,75 Y_NH3_B 0,25 S_Y_B

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]

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

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

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

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.

CFD Results of SGT-100 SGT-100 is an industrial gas turbine designed and manufactured at SIT Ltd, UK Power output ranging from 4.35 to 5.7 MW

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

Evaluation planes Measurements locations 6 points 4 PIV planes

Normalized Axial Velocity, Non-reacting flow CASE B

Normalized Radial Velocity, Non-reacting flow CASE B

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

Normalized Velocity, reacting flow CASE A PIV plane 1 PIV plane 2 PIV plane 3 PIV plane 4

Temperature, reacting flow CASE A

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

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

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, 2011. 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.

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, GT2011-45853, 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-2011-1122, 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-2011-0604, 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, GTIndia2012-9681, 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, GT2013-95454, 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, 25-28 June 2013. Lic. Thesis presented Nov 2011.

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