BOW-SHOCK STRUCTURE AND SLIP EFFECTS IN LOWDENSITY HYPERSONIC FLOW,

Hypersonic plane and axisymmetric flows around simple blunt shapes are treated within the framework of the Navier-Stokes equations, assuming a high compression ratio across the shock transition zone. The disturbed flow field is treated in two thin adjoining regions the shock layer and the shock-transition zone. The present investigations, which complement a previous devel opment Cheng 1963, provide an analytical solution for the structure of the bow shock and analyses of slip and temperature jump, as well as other higher-order effects. The formulation based on the two layers is shown to be consistent with the asymptotic expansion solution of the Navier-Stokes equations for high shock compression ratio and high Reynolds numbers. The present formulation provides uniformly valid approximations to the tangential velocity, temperature, streamline pattern and other properties of the whole flow field. The analysis of the structure of the bow shock takes into account the influence of the downstream flow nonuniformity on the shock profile. These results provide for the first time a description of the hypersonic flow field around a body without the usual shock discontinuity. For a highly cooled hyperboloidal shape at infinite Mach number a temperature maximum occurs inside the transition zone and a sharp frontal surface is observed which separates the disturbed flow region from the upstream uniform flow. Author