An investigation on heat transfer and fluid flow performance of serpentine-type microchannel heat sinks with a novel channel structure

Abstract

Microchannel heat sinks (MCHSs) are used to remove heat generated during the operation of electronic devices through flow channels. Therefore, they are regarded as a critical component of electronic systems in terms of both safety and performance. Traditional microchannel heat sink designs are considered inadequate for providing higher heat flux density and uniform temperature distribution. In this study, the heat transfer and fluid flow characteristics of a microchannel heat sink with a novel microchannel structure varying in channel depth from inlet to outlet are investigated with experimental and three-dimensional computational fluid dynamics model. After the numerical model has been validated with the experiment, parametric studies are performed for traditional MCHS with serpentine and straight flow fields, as well as new MCHS designs, according to the temperature uniformity index, thermal resistance, Nusselt number, performance evaluation criteria, and pressure drop. The 3–1 provides a maximum Nusselt number of 39.10, which is approximately 3.25 times greater than the straight MCHS design. In addition, the 3–1 design has the highest performance evaluation criteria of 1.90 and 2.67 when compared with the 1–1 and straight designs, respectively. The 1–3 and 3–1 designs have nearly the same minimum thermal resistance of 0.75 at a Reynolds number of 2000. There is no significant variation in temperature uniformity index of serpentine-type MCHS designs below a Reynolds number of 1250, and lowest temperature uniformity index is obtained with the 2–1 and 1–3 designs. Based on the results obtained, conventional straight flow field has the poorest heat removal performance.