Heat transfer optimization based on finned microchannel heat sink

The straight microchannel heat sink is relatively low in heat transfer efficiency due to the influence of the thermal boundary layer, and the thermal requirements of which may fail to be met under high heat flux conditions. In this paper, the fins were introduced to form a secondary channel to optimize the heat dissipation effect of the microchannel heat sink. Combined with CFD method, the structure parameters (the angle, lateral spacing and vertical spacing) and arrangement ways (the aligned, staggered) of internal fins in microchannel were analyzed. At the same time, CFD method is verified by experiments, and the relative errors are within 2%. Under the mass flow rate of 3.5 gs−1, compared with the straight microchannel heat sink, the maximum temperature and average temperature of optimized model are reduced by 3.04 K (6.67%), 2.86 K (6.75%), respectively. And the uniformity of temperature also is increased by 0.005 (8.47%). The pressure drop is reduced by 226.5 Pa (13.33%). At same time, the value of the performance evaluation can reach 1.285. In actual design and application, appropriate mass flow rate can be selected by the heating power to ensure the cooling effect of the microchannel heat sink and the power loss of the pump.