Method For Transition Prediction In High Speed Boundary Layers

The parabolized stability equations (PSE) are a new and more reliable approach to analyzing the stability of streamwise varying flows such as boundary layers. This approach has been previously validated for idealized incompressible flows. Here, the PSE are formulated for highly compressible flows in general curvilinear coordinates to permit the analysis of high-speed boundary-layer flows over fairly general bodies. Vigorous numerical studies are carried out to study convergence and accuracy of the linear-stability code LSH, and the linear/ nonlinear PSE code, PSH. Physical interfaces are set up to analyze the M=8 boundary layer over a blunt cone calculated by using a thin-layer Navier Stokes (TNLS) code, and the flow over a sharp cone at angle of attack calculated using the AFWAL Parabolized Navier-Stokes (PNS) code'. While stability and transition studies at high speeds are far from routine, the method developed here is the best tool available to research the physical processes in high-speed boundary layers. Parabolized stability equations, Compressible flows, High-speed boundary layers, General bodies.