Simulation of polymethyl methacrylate and hexamine sublimation with high temperature nitrogen in an axisymmetrical formulation

A computational technique has been created for modeling the sublimation of solid material in a high-temperature gas flow. The mathematical model and numerical algorithm have been verified using experimental data on the sublimation of hexamine at different gas temperatures at the reactor inlet. It is shown that the curvature of the sublimation front, on the one hand, is due to the presence of a boundary layer on the channel wall, and on the other hand, it can occur when heat transfer is intensified due to a decrease in the initial diameter of hexamine particles in the backfill. Parametric calculations of the dynamics of flow in a porous medium during the sublimation of polymethyl methacrylate and hexamine were performed. It is shown that different types of boundary conditions lead to different dynamics of the temperature behavior at the channel outlet.