Fluid Flow and Heat Transfer of Natural Convection Adjacent to Upward-Facing, Heated Plates Inclined Slightly from Horizontal

Natural convective flows over upward-facing, inclined plates were investigated experimentally. The attentions were focused on the opposing flows that will appear over the plates inclined slightly from horizontal. The flow fields over the plates and the surface temperatures of the heated plates were visualized with dye and liquid crystal thermometry. The result showed that both the descending and ascending flows appear over the plates when the inclination angle is less than 15°. These flows collide with each other at certain distance from the leading edge and, then, ascend away from the plate as a plume. It was found that the above distance is determined solely by the inclination angle and is independent of sizes and heat fluxes of the plate. The local heat transfer coefficients of the plates were also measured. The result showed that the heat transfer is enhanced slightly by the occurrence of the descending flows.