Wake characteristics of two-dimensional perforated plates normal to an air-stream

Abstract

The flow in the wakes behind two-dimensional perforated plates has been investigated in the Reynolds number range 2·5 × 10 4 to 9·0 × 10 4 . Measurements of drag and shedding frequency were made and a pulsed hotwire anemometer was used to measure the mean velocity and turbulent intensity variations in the highly turbulent regions immediately behind the plates. The results indicate the existence of two distinct types of flows: one appropriate to high and the other to low values of plate porosity.