An Experimental Study on the Upstream and Downstream Influences of Rectangular Cavities

Abstract

Experiments have been conducted on the separated and reattached flows of tunnel wall cavities along with relatively thick approaching boundary layers in incompressible flows. For very shallow cavities, approaching boundary layer thickness affects the base pressure whereas for deep cavities, its effect is minimal. In shallow cavities, the maximum pressure occurs slightly below the shoulder of downstream wall. In deep cavities the vortical flow will have sharp curvature of streamlines at the rear shoulder showing a higher static pressure.