Heat Transfer to the Turbulent Separated Flow of Air Downstream of a Step in the Surface of a Plate

Abstract

Experiments on a system in which separation of a turbulent boundary layer occurred at a downward step in the surface of a plate and reattached on the plate downstream of the step have produced additional results for the local heat-transfer coefficient and for the velocity and temperature distribution in the separated and reattached regions of the flow. In neither region was there found the kind of similarity near the wall that characterizes flows that are dominated by the friction at the wall, so that even this first element of the usual rationalization of the heat transfer is unavailable for the interpretation of the results. The effect of suction or injection through a slot at the base of the step is also indicated and this demonstrates relatively small effects on both the pressure distribution and the local heat-transfer coefficient.