Effect of Flow Maldistribution on Thermal Performance of Water-Cooled Minichannel Heat Sink

Flow maldistribution affects the cooling capacity of a water-cooled minichannel heat sink and cooling capacity of heat sink can be improved by minimizing flow maldistribution. Flow maldistribution depends upon the number of parameters such as flow rate, inlet/outlet position, and number of channels. This computational study has been performed using ANSYS Fluent 16.0 to investigate the effect of inlet/outlet positions and flow rate to delineate the flow maldistribution in minichannel heat sink. In this study, a minichannel heat sink with 28 numbers of rectangular parallel minichannels having hydraulic diameter 1.5 mm has been considered. Water and aluminum have been selected as a working fluid and heat sink material, respectively. In order to see the effect of inlet/outlet positions on flow maldistribution, four different types of inlet/outlet flow arrangements such as I-Type, Z-Type, C-Type, and U-Type have been considered. Effect of flow rate on flow maldistribution has been observed for the flow rate ranged from 0.5 to 1 LPM. Based on the results, it is found that flow maldistribution is strongly dependent on inlet/outlet positions and flow rate. Among all the arrangement, U-Type arrangement has small flow maldistribution which implies more uniformity in flow distribution in parallel minichannels and Z-Type arrangement has non-uniform flow distribution in parallel minichannels. It is also found that flow maldistribution affects the thermal performance of minichannel heat sink. A heat sink with U-Type flow arrangement has better thermal performance as compared to others arrangement.