An improved design of double-layered microchannel heat sink with truncated top channels

An improved design of double-layered microchannel heat sink (DL-MCHS) with truncated top channels was proposed. The advantages of the design were studied numerically by a three-dimensional solid-fluid conjugate heat transfer model. The better performance of the design was well demonstrated by comparison with the original DL-MCHS. The results indicate that there exists an optimal truncation position for the top channel to achieve the best DL-MCHS performance, where the coolant temperature in the top channel is approximately equal to that in the bottom channel. The optimal truncation position is determined by the trade-off between the cooling effect and heating effect of the top coolant. Then the effects of individual parameters including bottom channel length (L-x), channel number (N), channel-to-pitch width ratio (beta), and total pumping power (Omega) on the performance of the proposed design were investigated. It is found that for the original DL-MCHS with larger L-x, the cooling effect and heating effect of the top coolant are both enhanced compared to the design with smaller L-x. In this circumstance, an appropriate truncated design for the top channel can reduce the top coolant heating effect significantly without the loss of cooling effect. As a result, the advantages of the truncated concept become more obvious when applied in a DL-MCHS with larger L-x. As the same reason, for a specific design with larger N, smaller beta or smaller Omega, the truncated design is strongly recommended to enhance the DL-MCHS performance. (C) 2015 Elsevier Ltd. All rights reserved.