Sensitivity of hypersonic flow to wall/gas interaction models using DSMC

Studies of flow over a flat plate by the method of direct simulation using Monte Carlo (DSMC) are described; particular emphasis is placed on the influence of the wall/gas interaction model. Effects of the commonly used diffuse/specular combinations are compared with those for the baseline model employing fully accommodated diffuse molecular scattering. Computations using the baseline model are also compared with those for the lobular scattering model prepared by Hurlbut and Sherman on the basis of suggestions by Nocilla (HSN). Profound alterations from baseline distributions of the velocity and density fields are observed for specular/diffuse combinations and for the HSN models and significant effects on temperature distributions are also observed.