Effects of geometric parameters on fluid-flow and heat transfer in micro-channel heat sink with trapezoidal grooves in sidewalls

Trapezoidal grooves were arranged in channel sidewalls of the proposed micro-channel heat sinks to enhance heat transfer for cooling microelectronic systems. The 3-D numerical simulations were carried out to investigate the characteristics of fluid-flow and heat transfer in the proposed micro-channels. Field structures of thermal fluid-flow, Nusselt number, and friction factor, f, were employed to study the effects of the relative groove depth, alpha, and relative grooves spacing length, beta, of trapezoidal grooves on the thermal and hydraulic performance of the proposed micro-channels. The results showed that the proposed micro-channel presented better flow and thermal performance than the smooth straight one for Re <597.74 with f/f(0) < 1 and for Re >149.44 with Nu/Nu(0) > 1, respectively. The thermal enhancement factor, eta, was achieved up to 1.197 with alpha = 0.4 and beta = 1 for Re = 714.18. Furthermore, the relative groove depth had much more significant influence on the overall performance than the relative groove spacing length.