Numerical investigation of double layer microchannel heatsinks and performance assessment based on Taguchi method

Abstract

In this study, the performance of double-layer microchannel heat sinks was investigated by Computational Fluid Dynamics Analysis using the Taguchi Experimental Design Method. Selected parameters are Reynolds number, microchannel material, width of upper and lower channels, distance between these channels and heat flux. The effect of these parameters on the on-chip thermal resistance, the total thermal resistance and the pumping power requirement were investigated. The influence of the selected factors was investigated based on the average of the signal-to-noise (SN) ratios and the response table for the signal-to-noise ratios. Except for the total thermal resistance in the counterflow configuration, the Re number was found to be the most important factor for all other cases. Copper gives the best results due to its thermal dissipation characteristic. For the counterflow configuration, the effect of the heat flux on the thermal resistances is negligible except for the total thermal resistance. The effect of the width of the lower channel on the thermal resistances is more dominant than the upper channel. The lower and upper channel widths are equally important in terms of the required pumping power. There is an inverse relationship between channel width and required pumping power. The distance between the lower and upper channels is insignificant in terms of the required pumping power. If this distance is lower in a parallel flow configuration, on-chip thermal resistance is minimal. On the other hand, the total thermal resistance increases with this distance. As the channel widths increase, the average velocity in the channel decreases, so an increase in thermal resistance is observed.