Effect of surface ablation on aerodynamic heating over a blunt cone in hypersonic airflow.

This article focuses on the numerical simulation of hypersonic airflow around a blunt cone coupled with carbonaceous surface ablation to analyze how ablation reactions affect aerodynamic heating. It identifies three main ablative reactions—oxidation, nitridation, and sublimation—and distinguishes their thermal impacts as surface thermal effect (STE) and gas-phase chemistry thermal effect (GCTE). Under high Mach number conditions (Ma = 15.99), sublimation dominates near the stagnation point by absorbing heat on the surface (STE) while its products release heat in the boundary layer (GCTE), whereas downstream oxidation primarily influences heating through exothermic surface reactions with negligible gas-phase effects, and nitridation mainly contributes via exothermic gas-phase reactions with weak surface heating. At moderate Mach numbers (Ma = 10.2), oxidation dominates ablation effects, increasing surface temperature mainly through STE, with minimal GCTE. The study highlights that ablation-induced diffusion significantly increases the total incident heat flux, and mass ejection from ablation can carry away substantial heat, emphasizing the need to consider both STE and GCTE in thermal protection system design for hypersonic vehicles.