The impact of square shape perforations on the enhanced heat transfer from fins: Experimental and numerical study

Heat sinks are widely adopted as heat transfer boosters for their role in promoting heat transfer surface area. To enhance the thermal behaviour of heat sinks under forced convection heat transfer, perforated fins are utilized. In the present investigation, the effect of utilizing the square perforation technique has been experimentally and numerically investigated. The study was conducted for different numbers of perforations, i.e. 4, 6, 9, 12, and 15; heat supplied rates of 1730, 2200, 2680, and 3150 W; and airflow velocities of 0.4, 0.7, 1.1, 1.4, and 1.8 m/s. The present numerical results were validated against the present experimental results and available data in the literature, and excellent agreements were found. Our results indicated that the perforated fin with square perforations has shown a reduction in the fin temperature up to 16 degrees C compared to the non-perforated one. Moreover, by increasing the number of perforations, higher heat rates were dissipated because of the rise in the flow turbulence level and the reduction in the thermal resistance between the fin surface and its surroundings. In addition, the existence of perforations reduced the friction factor around the fin and sequentially reducing the required flow pumping power, which adds another merit to the aforementioned perforation technique. Using square perforations showed a 5.9% reduction in average friction factor compared to circular perforations.