Monte Carlo Radiation Model for Simulating Rarefied Multiphase Plume Flows

摘要

A Monte Carlo ray trace radiation model is presented for the determination of radiative properties of Al2O3 particles in the high altitude plume of a solid propellant rocket. A polydisperse distribution of non-gray particles is modeled as an emitting, absorbing and scattering medium of arbitrary optical thickness. Strong two-way coupling is allowed between radiation and flowfield calculations, where the gas is simulated using the direct simulation Monte Carlo method and particle phase properties are determined using a similar Lagrangian approach. Effects of anisotropic scattering and nozzle searchlight emission are considered, and a procedure is described for the calculation of spectral radiance. The model is applied to the simulation and radiation analysis of the freely expanding plume from a subscale solid rocket motor, and various flowfield properties are presented and discussed.