LES analysis of the DLR F400S.3 mGT burner operating with 100% hydrogen fuel

The paper approaches a computational evaluation of the 100% hydrogen fueled, DLR micro-Gas Turbine (mGT) burner F400S.3 through high-fidelity Large Eddy Simulations (LES). Sensitivity analyses on the thermal boundary conditions of the burner walls and the turbulent combustion model were conducted. The experimental OH*-Chemiluminescence distribution was compared with numerical results obtained using the Partially Stirred Reactor (PaSR) and the Extended Flamelet Generated Manifold (ExtFGM) combustion models. The results showed good agreement regarding the flame shape and reactivity prediction when non-adiabatic thermal boundary conditions were applied at the burner walls and the PaSR model was implemented. On the contrary, the ExtFGM model exhibited underprediction in flame length and flame lift-off, overestimating flame reactivity. Finally, after selecting the combustion model that best retrieved the experimental data, a pressurized LES was performed on the combustor domain to evaluate its performance under real operating conditions for mGT. • First high-fidelity study of DLR F400S.3 burner under atmospheric and pressurized conditions; fills literature gap. • CHT analysis captures wall heat loss in mGT burner, improving temperature predictions vs. adiabatic LES. • ExtFGM model includes flame stretch and heat loss/gain, improving non-adiabatic combustion accuracy. • PaSR vs. ExtFGM shows ExtFGM’s limits in capturing flame lift-off and length; highlights tabulated model gaps.