Experimental Study of Heat Transfer Enhancement With a Single Inclined Perforated Obstacle in a Rectangular Channel

Abstract

Measurements were carried out to investigate the enhancemen and the influence of flow friction in a rectangular channel usi perforated obstacle (baffle) affixed on the bottom surface whit uniform heat flux. A horizontal rectangular channel with an aspe of 1:5 was examined. The obstacle was attached to the heated aligned in the favorable direction of the flow. Both solid (wit perforated obstacles were used. The effects of perforation, obs between obstacle and upper surface were studied. The ope 0.023, 0.038, 0.115, and 0.167 were investigated and Reynolds 15000 to 45000. The experiments covered a range of obsta height ratio (UH) from 2.0 to 6.0, and gap to channel height r 0.7. Inclined perforated obstacle combines three major heat tra boundary layer separation, internal flow swirls, and jet impi showed that the maximum heat transfer enhancement and frict 3.7 and 11.0 times more than that smooth channel, respectivel were achieved using obstacle with (3 = 0.023, UH = 2.0, and B/ efficiency index was found for the obstacle with 13 = 0.167, L/H where, a maximum efficiency index of about 1.6 was found. N obtained for the influence of the parameters on both Nusselt and flow friction factor ratios.