Design analysis of minichannel heat sink with indented fins under impingement flow condition

Recent advances in transportation and new energy fields such as electric vehicles and power trains requires integrated power modules with increasing power input/outputs with high reliability. The next generation of integrated power inverter would have multiple MOSFET devices for demanding operations, leading to unprecedented challenges in thermal management, materials and reliability. In this work, the design and analysis of the minichannel heat sink under central impingement flow condition is analyzed for the purpose of cooling a high power module. The heat sink consists of a base plate populated with multiple minichannels and a cover plate with inlet and outlet connection holes. To avoid undesirable pressure loss, the central fins facing the inlet jet flow are cut out to reduce the flow resistance. The numerical model successfully implement the reduction of pressure drop with the indentation of the fins. The experimental measurements were conducted for an existing heat sink with central fin cutout and a cover plate for impinged flow subjected to a heating area of 30 mm × 30 mm, which is to verify the model development. A comparison of the numerical simulation with the experimental measurement demonstrates good agreement in both thermal performance and pressure drop. Furthermore, the additional pressure drop is reduced by the numerical optimization with various geometrical parameters. Geometrical factors such as inlet/outlet sizes, inlet transitional zone and impingement flow width are found to affect the pressure drop significantly. Geometrical and fluidic optimizations indicate the advantages of the present impingement flow with fin indentations.