In the present study, fluid-flow and heat-transfer characteristics of a microchannel heat sink subject to an impinging jet are experimentally investigated. In order to evaluate the cooling performance of a microchannel heat sink subject to an impinging jet under the condition of fixed pumping power, the pressure drop across the heat sink and temperature distributions at its base are measured. Specifically, a microthermal sensor array is fabricated and used to accurately measure temperature distributions at the base of the heat sink. Based on these experimental results, a correlation for the pressure drop across a microchannel heat sink subject to an impinging jet and a correlation for its thermal resistance are suggested. In addition, it is shown that the cooling performance of an optimized microchannel heat sink subject to an impinging jet is enhanced by about 21% compared to that of the optimized microchannel heat sink with a parallel flow under the fixed-pumping-power condition.
