Experimental Study of the Interaction between Internal and External Flows of a Scramjet Nozzle using Various Diagnostic Techniques

Kurzfassung

In the framework of a graduate student research group financed by the German National Research Council (DFG), an experimental study on nozzle flows was carried out at the German Aerospace Center (DLR). The tests were performed at a free-stream Mach number of 8 in the H2K wind tunnel at the DLR in Cologne. The Reynolds number was varied in order to simulate the influence of different flight altitudes of a scramjet vehicle. The effects of different nozzle pressure ratios have been investigated and compared. The static pressure distribution on the single expansion ramp was measured by the Pressure-Sensitive Paint (PSP) Method and PSI pressure transducers. A Pitot rake was used to measure the Pitot pressure distribution in the nozzle wake. Schlieren photographs are also used to investigate the flow field. The experimental results are discussed and compared with CFD calculations.