Numerical solutions to three-dimensional shock wave / vortex interaction at hypersonic speeds

A recent study at the University of Maryland has been undertaken to numerically solve the interaction flowfield between a helical-type vortex and an oblique shock wave. The study develops solutions to three-dimensional shock wave/vortex interaction at two Mach numbers, namely Mach 2.28 and 5.00.; The numerical model used is based on a scheme developed by P. A. Gnoffo of the NASA Langley Research Center. It is a finite volume, implicit upwind differencing method which is used to solve the integral form of the Euler equations.; In each case, a vortex was input into a flowfield containing a 46.4 degree shock wave. These solutions showed several interesting results. Because of the different angles which the vortex velocity vector would strike the shock wave an asymmetry across the post-shock vortex was observed. However, neither this asymmetry nor the pressure jump across the shock was enough to cause the vortices to breakdown. In fact the vortex strength did not change appreciably between the input and the post-shock vortex.; However, two unusual structures were observed. The first was common to both flowfields and was seen as areas of flow reversal around the outside of the post-shock vortex. The second unexpected structure was observed only in the Mach 5.00 flowfield and was seen as the formation of a trough-like structure around the outside of the post-shock vortex.; Further study is needed to determine the cause of these structures. They may possibly be a result of vorticity generation due to the nonuniform pre-shock flowfield combined with the shock curvature. To the best of the author's knowledge, this is the first time these two structures have been observed. They presented an interesting conclusion to this study.