Acceleration of a Hypersonic Boundary Layer Approaching a Corner

摘要

An asymptotic description of the acceleration of a laminar hypersonic boundary layer approaching a sharp corner is obtained. The description assumes small interaction with the outer inviscid flow. Viscous forces are neglected except in a thin sublayer. The initial part of the expansion takes place over a distance O(M sub e differential), where M sub e is the external Mach number, and differential is the boundary-layer thickness. Here the transverse pressure gradient is small, and a solution can be obtained analytically. Within a distance O(differential) from the corner, the effect of streamline curvature is essential, and a numerical solution is obtained by the method of integral relations for a single strip. The solution for surface pressure is compared with experimental results for a particular case,and an approximate velocity profile at the corner is calculated. Possibilities for improving the accuracy of the calculation, both by refining the numerical procedure and by including higher order effects, are considered. (Author)