Performance of novel liquid-cooled porous heat sink via 3-D laser additive manufacturing

Abstract

The performance of five water-cooled heat sinks is experimentally investigated. The test samples include the reference chevron-type corrugation, and four novel Body-Centered Cubic (BCC) porous structure. The proposed BCC structures include a homogeneous porous structure, non-uniform porous structure, non-uniform porous structure with augmented fin efficiency, and the non-uniform porous structure with augmented fin efficiency and inlet compactness design. The test samples are made from laser-powered metal additive manufacturing process having Titanium alloy as the construction materials. Test results indicated that the proposed BCC porous structure shows a much lower pressure drop than the traditional metal foam, and the proposed homogeneous porous BCC structure is superior to the reference chevron-type corrugation except at the low flowrate. The thermal resistance can be reduced about 55% at a pumping power of 1 W. The non-uniform porous structure can effectively force the working fluid toward the heating surface and results in an appreciable increase in heat transfer performance. With a further increase of the strut diameter at the lower part of the cold plate from 0.3 mm to 0.6 mm, the design with augmented fin efficiency shows the best performance among all test samples, the lowest thermal resistance reaches about 0.0118 K/W at a flowrate of 6 LPM. Yet this non-uniform porous structure with augmented fin efficiency outperforms all other structures in the entirely operational range. The proposed non-uniform porous structure with augmented fin efficiency outperforms most existing studies. (C) 2019 Elsevier Ltd. All rights reserved.