TOPOLOGICAL INTERPRETATION OF THE SURFACE FLOW VISUALIZATION OF CONICAL VISCOUS INVISCID INTERACTIONS/

The asymptotic flow structure is considered for a viscous-inviscid con ical interaction, in particular that between a swept shock wave and a boundary layer. A flow model is devised based on the three-layer inter action concept. Assuming conicity of the inviscid flow regions, a visc ous layer structure is established that is compatible with the invisci d outer how, and which produces a geometrically conical surface flow p attern. This result is obtained from a dimensional analysis, which rev eals similarity of the viscous layer in cross-flow planes at different radial distances from the conical origin. The results of this analysi s provide a tool for the quantitative interpretation of surface flow v isualizations in terms of the related topological structure of the flo w in the cross-how plane. This method is illustrated by application to the surface flow visualization of a Mach 3 shock-wave/boundary-layer interaction.