A two-phase MMC–LES model for turbulent spray flames

Abstract

A multiple mapping conditioning/large eddy simulation model (MMC–LES) is formulated for turbulent spray flames. Heat and mass transfer between the gaseous and liquid phases is modelled using a conserved scalar form of the Spalding transfer number approach along with an evaporative mixing model that is local in mixture fraction space. The model and the numerical implementation are tested in a non-reacting and two reacting experimental acetone spray cases. Model predictions are generally in good agreement with the velocity, liquid volume flow rate and mean temperature data and are shown to have a low sensitivity to the sparse stochastic particle resolution. The consistency of the heat and mass transfer coupling between the hybrid Eulerian–Lagrangian–Lagrangian schemes is demonstrated by comparison of mixture fraction fields solved on both the LES and the stochastic particles. A comprehensive appendix contains a derivation of the phase-weighted form of the MMC–LES governing equations along with a derivation and single-droplet test of the conserved scalar heat and mass transfer formulation.