Investigation of convective heat transfer from non perforated and perforated rectangular and pin fins for effective cooling of electric motors: A numerical approach

Abstract

This article presents a novel approach for enhancing heat transfer of electric motors by utilizing perforated fins through experimental and Computational Fluid Dynamics (CFD) technique to address the challenge of thermal management of electric motors through more heat dissipation. Electric motors (EM) are essential components of several industries; its longevity, dependability, and efficiency are all greatly impacted by its heat management. Earlier research on convective heat transfer from electric motors relied on traditional solid fins. Perforations improve convective surface area and fluid flow turbulence, which allows for greater heat dissipation. This article also presents a comparative numerical investigation of convective heat transfer from perforated and non-perforated rectangular and pin fins. The numerical simulations are performed using 3D CFD using ANSYS Fluent with K-omega turbulence model. Our results demonstrates perforated fins exhibit superior heat transfer performance compare to non-perforated fins, with an average percentage difference 95 % and 10 % for rectangular and pin fins, respectively. The centrally placed 10 mm diameter, 11 numbers perforations on the rectangular fins, provided highest rate of heat transfer, which was 54 Watt, whereas non-perforated fins dissipates only 19 Watt. Pin fins having three perforations provided 10.52 % increase in rate of heat transfer as compared to non-perforated pin fins. Comparing the results of three perforation pin fins and a 10 mm diameter perforated rectangular fin, it was found that the perforated pin fin reduces the volumetric mass by 31.1 % while the rectangular fins provide 28.5 % more heat transfer rate with 45 % more volumetric mass. This work concluded that, a rectangular perforated fin with a maximum perforation diameter provides a significantly high heat transfer rate when compared to all other combinations. In contrast, while concentrating on weight and cost reduction with small sacrifices of the rate of heat transfer, a perforated pin fin with three perforations can be considered for better thermal management of electric motors.