DOI: 10.1615/TSFP2
LARGE EDDY SIMULATION OF A HIGHLY TURBULENT METHANE FLAME: APPLICATION TO THE DLR STANDARD FLAME
ABSTRAKT
A Large Eddy Simulation in three dimensions is applied for the study of a highly turbulent methane flame. As target for this investigation, a flame with simple flow-field that burns without stability problems was a prerequisite, while this flame should not form soot to simplify laser-diagnostics. A good choice for this can be the DLR-Standard-Flame.
In the numerical method for the flow, fluctuations of density in space and time are considered to only depend on chemistry, not on pressure. To represent the sub-grid scale stresses and scalar flux, a Smagorinsky model is used in which the coefficient is determined by the dynamic Germano procedure. Density, temperature and species concentrations are related to the mixture fraction by a flamelet model. Subgrid fluctuation of the mixture fraction is described by a β - function.
The computed results are found in overall agreement with the experimental data. Only close to the nozzle of the fuel-jet gradients are too big to be resolved by the underlying numerics.