Sound Suppression of Laminar Separating Flow over Cavity

Abstract

A passive control of aerodynamic noise generated by a laminar separating flow over a cavity is carried out in a wind tunnel test and by numerical simulation, using a thin plate inserted into the cavity as a passive flow-controlling device. In the experiment, a noise suppression effect up to 14dB is achieved by placing a plate in a proper location. It is shown that a plate of smaller vertical size is more effective. In the numerical simulation, it is shown that the location where the shear layer rolls up and the path of vortices are both very sensitive to plate position.