Experimental investigation of ground effects on a heated cylinder in crossflow.

Abstract

The fluid flow and forced convective heat transfer characteristics of a uniformly heated right circular cylinder resting on a flat plate in a crossflow of air were experimentally investigated. The circumferential variation of the Nusselt number on the cylinder surface was obtained at Reynolds numbers ranging from 53,000 to 153,000 using a liquid crystal thermographic technique. Pressure coefficients were obtained at five-degree intervals around the cylinder circumference at Reynolds numbers of 105,000 and 156,000. Flow visualization was conducted at a Reynolds number of 10,000 in order to qualitatively examine the flow field. A qualitative theory based upon a compilation of previous results reported for flow around a "free" cylinder and flow over forward and rear-facing steps was developed. Experimental results obtained were in agreement with the proposed theory, and heat transfer and pressure data correlated well with one another. In the region between and 180 degrees, the heat transfer and pressure results correlated quantitatively with the results obtained by Meyer for a "free" cylinder at Reynolds numbers above 300,000.