Analysis of heat transfer and fluid flow in a microchannel heat sink with sidewall dimples and fillet profile

The performance of microchannel with sidewall dimples and fillet profile in the bottom surface is investigated. Two dimple sizes of (0.5 mm and 1 mm) are systematically clustered along the channels with and without fillet are considered. The laminar flow regime is assumed with Reynolds numbers ranging from 200 to 1200. The results show that the dimples and fillet profile have a significant effect on the thermal performance of microchannel. The Nusselt number of the microchannels with 1 mm dimples is 20% higher than the plain microchannel. However, an increase in pressure drop of 10% was obtained. In addition, the fillet profile impacts the thermal performance of microchannels without pressure drop penalty increase. Combining both dimples and fillet profile causes a significant enhancement in the thermal performance. Nusselt number of microchannels heat sink with 1 mm dimple size and fillet profile is 60% higher compared to the plain microchannel.