Transition and Turbulence Phenomena in Supersonic Wakes of Wedges

Abstract

At supersonic speeds the wake of a blunt body may be divided into an inner viscous wake stemming from the body boundary layers and an outer “inviscid” wake produced by the bow shock. In such wakes, as in the wake of a cylinder, at low Reynolds numbers the onset of transition occurs thousands of diameters downstream of the body in the outer, shock-induced wake. As the Reynolds number is increased, transition occurs in the inner wake. For the same Mach number and at high Reynolds numbers transition on the wake of a wedge occurs further downstream than in the case of a cylinder, but the slender body transition curve crosses the blunt body transition curve. The question arises, where does transition occur in slender body wakes as the Reynolds number is decreased further? What effect does the much weaker outer shock-induced wake have on transition and, is the outer wake unstable enough to become turbulent?