Influence of Surface Chemical Reactions on High-Altitude Aerothermodynamics of a Generic Capsule

A numerical study of a 3D flow about a generic spacecraft capsule is carried out for conditions corresponding to a flight at an altitude of 100 km. The SMILE++ code based on the Direct Simulation Monte Carlo method is employed in the computations. For the first time in 3D molecular kinetic simulations of high-altitude aerothermodynamics, heterogeneous processes on the surface of the thermal protection system of the capsule are modeled with detailed multi-stage kinetics. It is demonstrated that, even at high flight altitudes, surface recombination not only leads to a significant increase in the heat flux to the surface of the descent vehicle and its temperature, but can also produce a noticeable effect on its aerodynamic characteristics, such as pitching moment.