Hypersonic flows past a yawed circular cone and other pointed bodies

Abstract

A detailed treatment of inviscid hypersonic flow past a circular cone is given, for small and moderate yaw angles, within the fremework of shock-layer theory. The basic problem of non-uniform validity associated with the singularity of the entropy field is examined and a valid first-order solution is obtained which provides an explicit description of a thin vortical layer at the inner edge of the shock layer. Analytic formulas for pressure and circumferential velocity are given consistent to the second-order approximation including the non-linear yaw effect.The study of the entropy field (which is not restricted to the hypersonic case) also provides corrections to previous work on the yawed cone and confirms the validity of the linear yaw effect on pressure field in the Stone theory.A related investigation of three-dimensional flow fields is presented with special reference to the flow structure near the surface of a pointed, but otherwise arbitrary body. The inviscid streamline pattern on the surface is given by the geodesics originating from the pointed nose as a leading approximation of shock-layer theory. Associated with this streamline pattern is a vortical sublayer which exists generally at small as well as at large angle of attack. At the base of the sublayer, enthalpy and flow speed remain essentially uniform.