Influence of geometric parameters on flow and heat transfer performance of micro-channel heat sinks

Numerical simulations are carried out to investigate the influence of geometric parameters on the flow and heat transfer characteristics of rectangular, trapezoidal and triangular shaped microchannel heat sinks. A good agreement is found between numerical results and experimental data when the variation of water viscosity with temperature is taken into account. The microchannel with high aspect ratio, long wetted perimeter and small hydraulic diameters usually have low thermal resistance and high pressure drop. For the rectangular microchannel, it has the best performance with the aspect ratio among 8.904-11.442. And among three kinds of microchannel, the rectangle has the lowest thermal resistance, followed by trapezoid and triangle microchannel. The channel number also affects the thermal resistance and pressure drop. The increase of channel number reduces the thermal resistance, but at the expense of high pressure drop. Under the condition of the same power consumption, the channel number has an optimum range.