Drag and total power reduction for artificial heat input in front of hypersonic blunt bodies

The effect of an air-spike in hypersonic flow is considered in the paper. The similarity laws of shape dependence and shock wave parameters, as a function of the strength of the heat source and characteristics of incident flow, are given. The numerical modeling is performed, based on the Euter gasdynamic equations for conditions identical to those tested in the RPI Hypersonic Shock Tunnel (M=10.1), where heat deposition took place with and without a blunt body in the stream. Good agreement between the individual shock wave shapes given by asymptotic theory, numerical modeling, and experiment is demonstrated. Results of numerical modeling show significant drag reduction and confirm the energy efficiency of the air-spike concept.