Thick, Two-Dimensiorial, Turbulent Boundary Layers Separated by Steps and Slot Jets

The objective of this viscous interaction study was to investigate the separation phenomena which occur ahead of two-dimensional steps and slot jets. This investigation was restricted to the case where the height, /?, of the step or jet was less than the boundary-layer thickness, <5. The boundary layer, itself, was turbulent and adiabatic. The independent test variables selected were Red and h/6. The tests were performed in a two-dimensional, Mach 4.9 half-nozzle boundary-layer channel. Two glass-ported side pla were used to split off the thick sidewall boundary layers. The significance of two parameters, i.e., the Reynolds number and h/d, was revealed in the study; the degree of influence of either parameter decreased as its value increased. Three useful geometric scaling parameters were defined with the first scaling the initial steep pressure rise region and the second scaling the separation region of the total pressure profile. Use of these two distances permitted the development of a universal pressure profile. The third distance scaled the physical system by defining the standoff position of the separation shock in the freestream.