Book Description

An experimental investigation of the behavior of a turbulent boundary layer subjected to adverse and favorable pressure gradients was conducted at Mach number 4 for a free-stream Reynolds number of 0.500,000 per inch. Two severe pressure gradients were imposed on the boundary layer by interchangeable contoured centerbodies inside a large hollow cylinder for cold-wall and adiabatic-wall temperature conditions. Imposition of either of the adverse pressure gradients significantly decreased the natural growth rate of the boundary-layer displacement thickness, whereas the favorable pressure gradient had opposite effects; momentum thickness was relatively unaffected by pressure gradient. A pressure gradient increase of about 30 percent caused relatively small changes in the skin friction, heat-transfer rate, and the characteristic boundary-layer parameters. Wall cooling effects (T sub w/t sub 0 approximately 0.3) on the boundary-layer thickness parameters were nearly insignificant, in comparison with the adiabatic-wall results. Heat-transfer distributions were similar to the local skin friction results based on free-stream conditions. (Author).