Supersonic Turbulent Boundary Layer Subjected to Adverse Pressure Gradients

A set of experimental data is presented for a supersonic, two-dimensional turbulent boundary-layer growing along a flat wind-tunnel test section wall while subjected to a systematic variation of three adverse pressure gradients starting from the same initial conditions. The data are for a nearly adiabatic wall with an initial Mach number and Reynold's number per foot of 2.36 and 11.55xl06, respectively. Detailed profiles of pitot and static pressure, total temperature, mass flow, and turbulence intensity at four axial stations are presented along with direct measurements of wall shear. It is found that profile shapes are affected more by the magnitude than the character of the pressure gradient except very near the wall. Wall shear is found to increase with distance in the pressure gradient with this increase being a function of both the magnitude and character of the pressure gradient. The turbulence intensity is found to monotonically decrease with vertical distance in the zero pressure gradient region, whereas that in the adverse pressure gradient region increases between the wall and the middle of the boundary layer and then decreases to a relatively low freestream value. Comparison of the data with an exact numerical calculation based on an eddy viscosity approach indicates good agreement between profile shapes, but predicted values of wall shear are 8% to 20% low.