Thermal-hydraulic investigation on micro heat sinks with ribbed pin-fin arrays and single heating input: parametrical study

The electronic devices are facing the challenge of high heat flux. To improve the thermal and hydraulic performance of micro heat sinks with ribbed pin-fins and single heating input, the geometrical parameters, including shapes, arrangements, width and height, are numerically investigated. The results show that the micro heat sinks with arc ribbed pin-fins exhibit the best comprehensive performance comparing with triangle and rectangle ribbed pin-fins. Meanwhile, even for the single heating input, the staggered ribs arrangement exhibits better comprehensive performance than that of the in-line ribs arrangement the same Reynolds number. Moreover, the average Nu number increases first and then decreases with the increase in the rib width. At Re = 1342, the average Nusselt number of D-p/D-0 = 1/2 can reach up 44.3, which is 1.8 times of D-p/D-0 = 3/2. Increasing the H-p/H-0 plays a positive effect on improving thermal performance but with higher pressure loss. At higher H-p/H-0, increasing H-p/H-0 does not show obvious effect on reduction total thermal resistance under the same pump power. To better balance the thermal resistance and pressure drop, the value of D-p/D-0 and H-p/H-0 should be chosen properly.