Investigation of thermal performance of microchannel heat sink with triangular ribs in the transverse microchambers

A numerical investigation is conducted to predict the thermal and hydraulic performances of the microchannel heat sink (MCHS) with different geometric parameters of triangular rib in the transverse microchamber. The parametric variables of width, length and height of the triangular rib are studied to find optimum design. The flow structure and characteristics of the interrupted MCHS are interpreted in details. The dimensionless ratios of average Nusselt number, friction factor and thermal enhancement factor are evaluated. It is found that the heat transfer rate is increasing with the increase of rib width and height, but decreasing with the increase of rib length. The boundary layer interruption and redevelopment effects introduced by the triangular rib are discussed. The results of thermal enhancement factor reveals an optimum geometrical parameters for the triangular rib with width = 100 μm, length = 400 μm and height = 120 μm for about Reynolds number of 500, yielding 43% enhancement relative to non-interrupted rectangular MCHS at equal pumping power. The results of mean Nusselt number ratio reveal an optimum enhancement of 56% relative to non-interrupted MCHS.