| A database of simultaneous wall-pressure array and particle image velocimetry (PIV) measurements was compiled for the investigation of the surface-pressure and the velocity signature of the structure within a separated/reattaching flow region. The experimental setup consisted of a long, splitter plate instrumented with an array of 80 flush-mounted microphones located within the wake of a fence. Data were acquired for two Reynolds numbers of 7885 and 10513, based on the fence height. Two distinctive regions, defined based on their location relative to the position of the mean reattachment point (xr) of the shear layer, emerged from the spatio-temporal analysis of the surface pressure measurements. Upstream, from the fence to ¼xr, the surface-pressure signature was dominated by large time scale disturbances and an upstream convecting velocity of 0.21Uinfinity. Beyond the ¼xr, turbulent structures with small time scales and a downstream convection velocity of 0.57U infinity generated most of the pressure fluctuations. There was evidence that these structures began to form around ¼xr and grew in strength and size with downstream distance before reattaching on the plate. Only the time-averaged results from the microphones at the lower Reynolds number have been examined hitherto and will be presented. |
