Influence of particles on radiative base heating from the rocket exhaust plume

The modified discrete-ordinates method with a two-phase mixture of nongray gases and a cloud of particles is applied to investigate the radiative base heating due to plume and searchlight emission. To obtain the radiative heat flux on the base plane, the exhaust plume is considered as an absorbing, emitting, and scattering medium, while the environment between plume boundary and rocket base plane is assumed nonparticipating. The radiative properties involving nongray gas and particle behavior are modeled by using the weighted sum of gray gases model with particles. After validating the present two-phase radiation solutions, numerical investigations are made to examine the effects of such various parameters as particle concentration, scattering phase function, particle temperature, and nongray gas composition on the radiative base heating in an isothermal cylindrical plume with nongray gases and AI₂O ₃ solid particles. The radiative base heating increases as the particle concentration and temperature increase. The forward scattering of particles increases plume emission while it decreases searchlight emission. The gas composition, however, does not significantly influence the radiative base heating.