An experimental study of a reattaching supersonic shear layer

A Mach 1.83 fully developed turbulent boundary layer was separated at a 25.4 mm backward step and formed a free shear layer. The incoming boundary layer thickness, momentum thickness, and Reynolds number were approximately 8 mm, 0.5 mm, and 52x10 to the 6th/m, respectively. A two-component coincident LDV system was used to take velocity measurements of the incoming boundary layer, the free shear layer, and the reattached shear layer. The results confirmed the existence of organized structures in both the free and the reattached shear layer which was reported earlier based on the authors dynamic pressure measurements and Schlieren photographs.