Effect of baffle size, perforation, and orientation on internal heat transfer enhancement

An experimental investigation of frictional loss and heat transfer behavior of turbulent flow in a rectangular channel with isoflux heating from the upper surface is presented for different sizes, positions, and orientations of inclined baffles attached to the heated surface. Both solid and perforated baffles are used. Inclined perforated baffle combines three major heat transfer techniques, e.g. boundary layer separation, internal flow swirls, and jet impingement. Results indicate that there exists an optimum perforation density to maximize heat transfer coefficients and this optimum perforation exhibits a strong jet impingement technique from the lower confined channel along with other enhancement techniques of heat transfer. (C) 1998 Elsevier Science Ltd. All rights reserved.