Effects of flow inlet angle on flow maldistribution and thermal performance of water cooled mini-channel heat sink

The cooling capacity of the mini-channel heat sink can be increased by making the flow distribution uniform through all the parallel mini-channels. The present study proposes a minichannel heat sink with modified novel inlet/outlet arrangement with different flow inlet angle such as (theta = 90 degrees, theta = 105 degrees, and theta = 12 degrees 0) for better flow distribution and heat transfer performance. This proposed minichannel heat sink has been analyzed numerically with the help of ANSYS-Fluent. Water is used as a working fluid and aluminum is selected as a heat sink material. Total 28 numbers of parallel mini channels are considered having the hydraulic diameter of 1.5 mm. It is found that flow distribution changes with this flow inlet angle and minimum flow maldistribution is observed for proposed inlet/outlet arrangement with theta = 105 degrees and results in better and uniform cooling of the heat sink. Further increment in flow inlet angle increases the non-uniformity of flow. The thermal performance also has been found best for theta = 105 degrees and the value of maximum base temperature was also lowest for this configuration. It is suggested that the performance of mini channel heat sink can be improved if coolant enters the distributor header with flow inlet angle theta = 105 degrees and exit from the middle of the collector header.