Experimental investigation of the two-phase heat transfer performance of a novel hybrid jet impingement microchannel heat sink subject to dielectric fluid HFE-7000

This study examines the two-phase heat transfer and frictional performance of a novel hybrid jet-impingement microchannel heat sink (HJIHS) for high-flux electronic devices. The proposed HJIHS contains an array of jets at its core. The array jets have a diameter of 1 mm and a pitch of 1.5 mm. Tests are conducted in a microchannel heat sink with 52 mm in length and 49 mm in width, and dielectric fluid HFE-7000 is used as the coolant. The microchannel features a width of 0.2 mm, a thickness of 0.2 mm, and a height of 3 mm. A typical cross-flow microchannel with identical geometry is also used for comparison. It is found that the hybrid jet heat sinks can dissipate a heat flux up to 55 W/cm 2 at a mass flux of 142 kg/m 2 ·s. For a mass flux near 144 kg/m 2 ·s and a heat flux about 40 W/cm 2 , the performance of HJIHS is about 4 % higher than cross-flow microchannel heat sink. The present design showed a 140 % lower pressure drop than the cross-flow microchannel at a heat flux of 40 W/cm 2 heat flux and a mass flux of 100 kg/m 2 ·s. The thermal spreading resistance contributes approximately 70 % of the total thermal resistance .