Simplified radiative models for low-Mach number reactive flows

We introduce a class of numerical models for the simulation of radiative effects in low-Mach number reactive flows. These models are based on simplified PN approximations for radiative heat transfer, low-Mach asymptotic in the compressible flow, and reduced four-step chemical reaction for reacting species. The models presented here remove on one hand, acoustic wave propagation while retaining the compressibilty effects resulting from combustion and on the other hand, simplify the integro-differential equation for radiative transfer to a set of differential equations independent of the angle variable and compatible to those used for modelling flow and combustion. We briefly discuss the basic discretization methodology for the combined equations and its implementation in a modified projection method. We present validation computations for a two-dimensional methane/air flame in which the computational results are compared for nongray participating media.