Effect of Taper and Perforation on Heat Transfer Coefficient of a Passive Horizontal Heat Sink

Abstract

The present study focuses on the numerical investigation of a passive horizontal base heat sink with perforated fins. Fins of the rectangular and trapezoidal cross-section are considered for the study. A detailed parametric numerical study is carried out considering the thickness ratio range (0.33–1); 4–6 mm size of square perforation; 6, 12, and 18 number of perforation and Rayleigh number 592–3044. Significant effect of thickness ratio, size of square perforation, and the number of perforations is observed on the heat transfer coefficient. The heat transfer coefficient increases with the decrease in the thickness ratio and increases with the number of perforation and size of square perforation in trapezoidal cross-section fins. 11.7% of increment in heat transfer coefficient was observed in perforated heat sink when it is compared to the non-perforated heat sink. Mass of the passive heat sink decreases with an increase in the size of perforation, number of perforations, and decrease in the thickness ratio. Mass reduction of up to 58% is observed in perforated heat sinks. A significant improvement in the performance factor is observed for the present study parameters range of Rayleigh number, the thickness ratio, size of perforation, and the number of perforations.