LES of unstable combustion in a gas turbine combustor

Investigation of lean premixed combustion dynamics in a gas turbine swirl-stabilized combustor is numerically conducted-based on Large Eddy Simulation (LES) methodology. Premixed flame modeling is based on the flamelet (G-equation) assumption. Unsteady flame behavior is successfully captured inside the combustor. The unstable flame motions are mainly governed by acoustic resonance, velocity field fluctuations and heat release fluctuations. They are in phase and coupled to sustain combustion instabilities. Future combustion control will lie in how to change these links. It is demonstrated that numerical methods based on LES are effective in comprehending real-scale combustion dynamics in a combustor.