Laminar Smoke Point Based Subgrid Soot Radiation Modeling Applied to LES of Buoyant Turbulent Diffusion Flames

Abstract

Large eddy simulations (LES) of gaseous buoyant turbulent flames have been conducted with the application of a flamelet based soot-radiation model. The subgrid model applies a turbulent eddy description of soot formation, oxidation and radiation and is based on the laminar smoke point concept. Two parameters, a local turbulent strain rate and prior enthalpy loss/gain fraction influence the soot formation and radiation. Radiation heat transfer is simulated by solving the finite volume discretized form of the radiative transfer equation (RTE) with the subgrid soot-radiation model implemented. The radiant heating of surfaces in close proximity of the flames is computed and predicted heat fluxes and surface temperatures are compared against experimental data. Fire growth in a rack storage arrangement is simulated with the application of a pyrolysis model. Computed heat release rate (HRR) is compared against experimental data.