On the Two-dimensional Compressible Flow over a Thin Symmetric Obstacle with Sharp Shoulders Placed in an Unbounded Fluid and in a Choked Wind Tunnel

Abstract

The transonic flow past a two-dimensional symmetric body with sharp shoulders placed in an unbounded compressible fluid and in a choked wind tunnel is studied by the use of the model flow, where the flow is assumed to separate from the surface of the body at the shoulder in stead of performing the Prandtl-Meyer expansion. Applying this model flow method to the flow past a finite wedge, and comparing with the more accurate solutions derived by Guderley, Cole, Hida and Marschner, it is found that the accuracy of the predicted values of the pressure distribution over the surface or the head drag coefficient is fairly good, but that as for the choking Mach number this model flow gives a rather different value from that of the real flow. The pressure distributions over the surface of the several symmetric profiles with sharp shoulders are calculated by this model flow method.