Hydrothermal performance of inline and staggered arrangements of airfoil shaped pin-fin heat sinks: A comparative study

The distinctive airfoil shaped pin-fins offer minimal resistance to fluid flow and enormous effective area due to the delayed fluid separation at the tail. In this article, the hydrothermal performance of inline and staggered arrangement of airfoil pin-fins heat sink for electronic systems was experimentally evaluated in a systematic manner. The comparative study was carried out by varying the Reynolds number and heating power ranging from 600 to 860 and 75 W to 125 W, respectively. To ensure the same surface area, the number of pin fins was identical in both configurations. Nusselt number, thermal resistance, pumping power, and overall performance were the examined parameters. Interestingly, the Nusselt number for inline arrangement of pin fins was observed to be higher, while the overall performance of the staggered configuration was revealed to be better. This could be caused by the increased pressure drop in the inline arrangement of pin fins. Experimental results revealed that the Nusselt number for inline configuration was almost 3.96 % higher than staggered arrangement at the highest heating power. In addition, the penalty of pumping power was also observed to be more for inline configuration. It was noted that to pump fluid at the same rate, an average of approximately 2.93 % more power would be required for inline geometry. A significant improvement in heat transfer was observed with a substantial drop in pumping power while increasing the heating power. Finally, the overall performance was examined, revealing that the staggered arrangement delivered better results. In comparison, a maximum of 1.81 % improvement in overall performance for staggered geometry was determined at 75 W, which reduced as heating power increased.