Investigation of heat and drag reduction in hypersonic rarefied environments using spike-aerodisk-opposing jet configurations

Heat and drag reduction are critical challenges in the aerodynamic and thermal design of near-space hypersonic vehicles. In this study, the implicit multiscale discrete velocity method is employed to investigate the aerodynamic and thermal characteristics of a spike-aerodisk-opposing jet configuration in rarefied hypersonic flows. The effects of flight altitude, Mach number, opposing jet intensity, and angle of attack are systematically analyzed. Results show that with increasing flight altitude, the freestream becomes more rarefied, leading to a gradual decline in the heat and drag reduction performance of the configuration. As the Mach number increases, the compressibility of the freestream gradually intensifies, resulting in a reduction in the heat and drag reduction capabilities of the spike-aerodisk-opposing jet configuration. In contrast, stronger opposing jets expand the influence region of the flow field, effectively improving both drag and heat reduction compared with the spike-aerodisk configuration alone. With increasing angle of attack, the effective windward area exposed to the flow enlarges, progressively degrading the mitigation performance; notably, when the angle reaches 25^∘, drag augmentation is even observed. Overall, the present study demonstrates the feasibility and robustness of the spike-aerodisk-opposing jet configuration for integrated drag and heat reduction in rarefied hypersonic regimes, offering valuable guidance for the aerodynamic and thermal design of reusable near-space hypersonic vehicles.