An investigation to determine the effects of highly underexpanded free jets impinging upon an adjacent flat surface has been conducted. The experimental program conducted in the Langley 4l-foot vacuum sphere consisted of obtaining pressure measurements and high-speed schlieren photographs. Unheated air (of approximately 2, 400 lb/sq in. abs) was exhausted from two different nozzles, a converging nozzle (jet exit Mach number, 1.0;nozzle exit diameter, 0.125 inch) and a converging-diverging nozzle with a nominal design Mach number of 5-0 having a nozzle exit diameter of 0.625 inch. The jet-impingement surface was mounted parallel to the nozzle axial center line and the distance of this surface from the nozzle axis was varied for each of the test nozzles. Continuous data were obtained over a range of ratios of jet total pressure to ambient pressure varying from about 250,000 down to 20,000.
展开▼
