In this paper, we investigate the extension of the flamelet-generated manifold (FGM) method to include preferential diffusion effects in methane-hydrogen-air flames. The FGM technique is a method to simplify the chemical kinetics model, which has been proven accurate for the modeling many type of flames. Due to the high diffusivity of hydrogen, flames in methane-hydrogen blends have a characteristic cellular structure, which is caused by thermal-diffusive instabilities. To account for preferential diffusion effects an additional degree of freedom is used to describe the combined fluctuations in enthalpy and element mass fractions. This approach is used to perform direct numerical simulations of lean premixed flame kernels in a turbulent flow field. The results are compared with results of simulations employing the full chemistry model. Extension of the manifold with one dimension appears to be enough for accurate predictions of species concentrations and burning velocities.
|Title of host publication||Fifth European Conference on Computational Fluid Dynamics, ECCOMAS CFD 2010, Lisbon, Portugal,14-17 June 2010|
|Editors||J.C.F. Pereira, A. Sequeira|
|Place of Publication||Portugal, Lisbon|
|Publication status||Published - 2010|