Variable protrusion density for an enhanced thermo-hydraulic performance in a microchannel

Abstract

With the growing importance of Artifical Intelligence in the future, the demand of highly effective and efficient microelectronics is raising. A microchannel with a high thermo-hydraulic performance would solve the problem. Feasibility of a durian profile microchannel has been proven and a variable fin density profile has shown promising thermo-hydraulic performance. Therefore, a combination of the two aforementioned concepts was presented and investigated. A microchannel with a microscale gap of 300 µm was created by inserting a solid cylinder with a diameter of 19.4 mm into a hollow cylinder with a diameter of 20 mm. Variable protrusion density is implemented in the surface profile design of the solid cylinder. Three surface profile designs, namely Uniform, Increasing, and Decreasing profile are introduced to investigate the effect of variable protrusion density on the heat transfer and hydrodynamic performances of the microchannel. Numerical investigations are conducted to provide insights into the fluid flow in the microchannel under different flow rates at a constant heat flux of 53 W/cm2. The heat transfer enhancing mechanisms were investigated and discussed. The wall temperature and local pressure along the flow direction were also discussed. The highest heat transfer coefficient recorded is 59.7 kW/m2∙K with a 1.7 bar pressure drop at 7 L/min, achieved by the Uniform density profile. The highest pressure drop across the microchannel is 2 bar at 7 L/min, experienced by the Increasing density profile