Reducing Aerodynamic Heating by the Opposing Jet in Supersonic and Hypersonic Flows

Abstract

The opposing jet is proposed for aerodynamic heat reduction. In this study, the opposing jet has been applied to three nose configurations including the ogive body, the hemispherical nose cylinder and the ogive body with the extended nozzle, to investigate the effects of nose configuration for the opposing jet. Numerical studies have been implemented for the supersonic flow at M∞ = 3.98, and for the hypersonic flow at M∞ = 8.0. Consequently, the opposing jet reduces aerodynamic heating both in supersonic and hypersonic flows. The results also shows that there is a direct correlation between the nose configuration and the thermal protection effect of the opposing jet, and of all three configurations, the extended nozzle model is found to be the most efficient configuration. In addition, detail flow field analysis revealed that distinct correlations exist between shock stand-off distance and the momentum ratio, and between local maximum heat flux and local Reynolds number at the reattachment point for the cases of turbulent flow reattachment. As a conclusion, it has been found that recompressed shock management and local Reynolds number management are essential in order to reduce aerodynamic heating by the opposing jet.