FLOW VISUALIZATION AND HEAT TRANSFER IN FREE CONVECTION OVER SLIGHTLY INCLINED SURFACE-MOUNTED PRISMS

摘要

This experimental study deals with convective heat transfer and flow features in the vicinity of an array of 3D short insulated surface-mounted square cylinders along an inclined plate and under uniform heat-flux density conditions. The experiments were conducted in water with the use of poor conductivity prisms so that both conduction and radiation effects could be neglected. Experiments on the flow and heat transfer were performed for slight inclination angles varying clockwise in the range -20° to +20° around the vertical position. Flow visualizations were carried out with particle-streak and dye-emission techniques to examine the flow field around the protrusions. The experimental analysis highlighted the strong influence of the plate inclination angle on the formation of rotational flows, 3D transverse flows, and separation phenomena in open cavities. Moreover, the positions that best enhanced heat transfer were found to be those corresponding to the positive angle range where 3D transverse flaws occupy all open cavities.