Thermo-hydraulic performance of wavy microchannel heat sink with oblique grooved finned

One of the crucial phenomena to enhance the heat transfer of micmchannel heat sinks is the flow mixing and wall interaction through the secondary flow. In the present study, a combination of the wavy and the oblique grooved microchannel patterns was investigated to improve the performance of the microchannel heat sink. The oblique grooves with a pitch of 375 mu m were combined with the wavy microchannel. The effect of fins with widths of 250 and 125 mu m on thermal performance was investigated (Type-1 and Type-2). The amplitude of 250 mu m and wavelength of 2500 mu m were considered for wavy microchannels. Furthermore, the effect of pitches on the heat transfer was studied; subsequently, pitches of 750 and 1500 mu m were analyzed (Type-3 and Type-4). Nusselt number, pressure drop, and performance evaluation criteria index were reported as the results. The results showed that secondary flow generation causes the thermal boundary layer to re-develop at each fin, continually developing fluid flow. Type-2 had the maximum average Nusselt number of approximately 80 and a pressure drop of approximately 50 kPa at Re = 850 compared to the other three cases. The performance evaluation criterion index (eta) was calculated for all cases to achieve a comprehensive conclusion about the performance of a heat sink. The results showed that in Type-2, the heat transfer increase exceeded the pressure drop penalty, and its eta was almost 2.5. Fluid flow patterns were investigated in detail as the most significant reason for efficiency improvement, and the wetted area was studied, which their maximum value equaled 1.2 at Type-2.

Automated summary

A combination of wavy and oblique grooved microchannel patterns was investigated to improve the performance of microchannel heat sinks. Type-2 showed the best heat transfer performance and pressure drop behavior, with an eta value close to 2.5.