Research on a novel combined shock control mechanism for thermal protection and drag reduction in hypersonic compressible flow field

Abstract

Aerodynamic heating and extreme shock drag are major problems faced in hypersonic compressible flow fields. This paper proposes a combined flow control mechanism that combines the advantages of spike, lateral jets and aero-disc. The effects of the combined mechanism in reducing aerodynamic heating and changing the flow field structure were studied by computational fluid dynamics. The physical model is a two-dimensional axisymmetric blunt body model with a novel combination mechanism. The numerical model is the coupling of the two-dimensional axisymmetric Reynolds averaging method and the SST model. The accuracy of the numerical calculation model and calculation method is verified by comparing with the experimental data in the literature. The results show that the new combination mechanism can effectively reduce the heat flow on the surface of the blunt body, and can be used as a new type of hypersonic compressible flow field thermal protection system (TPS). The research results show that appropriately reducing the Mach number of the lateral jet and increasing the total pressure ratio of the lateral jet can further expand the subsonic recirculation zone and reduce the intensity of the reattachment shock wave. This can effectively improve the thermal protection and drag reduction efficiency of the combined structure, but put forward higher requirements on the heat resistance and mechanical strength of the upper spike. At the same time, the influence of different jet angle on thermal protection performance, drag reduction effect and changing shock structure performance is further studied. The results show that the negative jet Angle is more conducive to the effect of cooling gas, while the positive jet Angle is more conducive to the effect of changing the shock structure in hypersonic flow field.