Effect of multiple pairs of vortex generators on the thermal performance of plate fin heat sink

In this paper, the heat transfer characteristics of multiple pairs of vortex generators (VG) mounted on vertical plate fins of plate fin heat sink (PFHS) are evaluated using computational fluid dynamic simulations. The delta winglet pairs are used as longitudinal VGs, and they are mounted one after the other in the axial direction. Critical design parameters for the double pair of VGs (DPVGs) are identified, and a design of experiment-based simulations is carried out to develop a response surface model for Nusselt number and thermal hydraulic performance parameter. Results show winglet length is a critical design parameter compared with winglet height, and the axial inter VG distance between VG pairs plays a crucial role in improving the heat transfer characteristics. The optimum inter VG distance for a double pair of VG is evaluated, and it is 2.2 to 3 times the length of the delta-winglet. Thermal hydraulic performance of PFHS with double pair of VG is 1.49 times higher than that of plain PFHS. Finally, the variation of heat transfer characteristics against velocity is also evaluated for the PFHS with a DPVG.