Convective heat transfer from simulated air-cooled printed-circuit board assembly on horizontal or vertical orientation

An experimental and numerical analyses had been performed to investigate the convective hear transfer in a rectangular duct flow with streamwise-periodic rectangular heated ribs mounted on one of the principal walls, which simulated a printed-circuit board (PCB) assembly. Experimental investigation were carried out with the PCB assembly orientated in both horizontal and vertical positions. Effects of varying the duct's height, and the rib's height and width on convection from the rib's surface to the air-flow were studied. The heat transfer measurements were obtained for unencumbered height-based Reynolds number from 510 to 2050. Predictive correlations valid over a range of Reynolds numbers, duct height-to-rib height ratios (WE) and rib's width-to-height ratios (VB) were proposed. (C) 1998 Elsevier Science Ltd.