On secondary destabilisation of an attachment line boundary layer in compressible flow

Kurzfassung

The generalised Hiemenz model is used to describe incompressible flow in the infinite swept attachment line boundary layer. This base flow is perturbed using local spatial LST and the resulting secondary instability problem is solved at high Reynolds numbers, extending earlier work. Issues raised by compressibility are discussed next; in the absence of a simplifying theoretical assumption, such as that of Görtler & Hämmerlin, we proceed to design a DNS in order to study the instability in question. The algorithm is outlined and first results on its successful application on a relevant compressible model problem are presented.