Wind tunnel experiments have been conducted under highly turbulent and disturbed flow conditions over a solid/perforated plate with a long splitter plate in its plane of symmetry. The effect of varied level of perforation of the normal plate on the fluctuating pressures measured across and along the separation bubble has been studied. The distribution of the unsteady surface pressures with variation of the perforation level of the normal plates is also studied. The different perforation levels of the normal plate that is 0%, 10%, 20%, 30%, 40% and 50% are studied. The Reynolds number based on step height is varied from 4×103 to 1.2×104. It is interesting to note that for 50% perforation of the normal plate, the RMS pressure fluctuation in the flow field gets reduced to around 60% as compared to that for solid normal plate. Analysis of the results show that the maximum fluctuating surface pressures as well as the fluctuating pressures in the flow field can be well correlated.

Abstract

2006