Spectral and Probability-Density Nature of Square-Prism Separation-Reattachment Wall Pressures

TLDR: In this article, the statistical nature of fluctuating pressures associated with the separation-reattachment flow were studied for a two-dimensional square prism in uniform flow for low (0.33 percent) and high (10.4 percent) turbulence levels.

Abstract: The statistical nature of the fluctuating pressures associated with the separation--reattachment flow were studied for a two-dimensional square prism in uniform flow for low (0.33 percent) and high (10.4 percent) turbulence levels. Studies were also made with a splitter plate to inhibit the feedback effect arising from vortex shedding. The nature of the separation--reattachment flow was characterized by use of the measured value of the mean and fluctuating pressure fields. Spectral distribution of the unsteady pressures reveals strong energy spikes at the Strouhal frequency which are eliminated by the presence of the splitter plate. Probability density distributions indicate appreciably non-Gaussian nature only in the wake. Additional information is presented on the variation with angle of the Strouhal frequency for the wake flow.