Modelling of a turbulent premixed flame series using a new MMC-LES model with a shadow position reference variable

Abstract

A new multiple mapping conditioning model with a shadow position reference variable for localising mixing is implemented in a large eddy simulation solver and validated against three experimental turbulent premixed flames. The shadow position used here has diffusion coefficient which is linked to the turbulent propagation speed. Localisation of mixing produces a flamelet-like inner structure in shadow position space and the structure in physical space is determined by the subgrid dispersion of shadow and physical positions. The lengths of the predicted flames match the trends observed for the experimental flames, and the predicted inner structures are consistent with what is expected for these flames in the thin reaction zones regime. The statistical predictions are in very good quantitative agreement with the experimental data for velocity and major species. Errors for reaction progress variable, turbulent kinetic energy and minor species (carbon monoxide) are generally larger yet mostly within the ranges reported in the literature.