| An experimental investigation was conducted to study the interaction between a shock wave and a turbulent boundary layer. The boundary layer was formed on the floor of a wind tunnel operating with a freestream Mach number of 2.94. Compression corner models, or ramps mounted on the wind tunnel floor, were used to generate the oblique shock wave. Ramp angles of 8(DEGREES), 12(DEGREES), 16(DEGREES), 20(DEGREES), and 24(DEGREES) were used to produce the full range of possible flowfields, including flow with no separation, flow with incipient separation, and flow with a significant amount of separation. Measurement techniques used in this investigation included Schlieren photography, surface static pressure measurement, surface streak pattern measurement, and laser Doppler velocimetry. The LDV system was used to make two component coincident velocity measurements within the redeveloping boundary layer downstream of the interaction. The results of the LDV measurements indicated that the boundary layer was significantly altered by the interaction. The mean streamwise velocity profiles downstream of the separated compression corners were very wake-like in nature, and the boundary layer profiles downstream of all the interactions showed an acceleration of the flow nearest the wall as the boundary layers began to return to equilibrium conditions. The streamwise turbulence intensity and the Reynolds stress within the redeveloping boundary layers were increased by the interaction, with the amount of increase directly related to ramp angle. Both quantities reached maximum values in the central regions of the boundary layers, with the vertical locations of the maximum values also directly related to ramp angle. Several features of the redeveloping flow, including high rates of boundary layer growth, large Reynolds stress values, and large turbulent triple product values, indicated the presence of large scale turbulent structures within the turbulent boundary layers downstream of the shock wave-boundary layer interactions. |
