Experiments are performed to investigate saturation boiling of degassed PF-5060 dielectric liquid on micro-porous copper dendrites surface layers deposited on 10 × 10 mm Cu substrates. The electrochemically deposited surface layers are of different thickness (50, 70, and 220 μm), average pore size (15, 30 and 80 μm) and volume porosity (96, 94.3, and 93.6%). The thickest layer, deposited using 3.0 A/cm2 for 25s, gives the best results: the saturation CHF of 25.27 W/cm2 occurs at a surface superheat of only 2.9 K and the maximum nucleate boiling heat transfer coefficient, hMNB, near the end of the fully developed nucleate boiling region is 8.76 W/cm2.K. In addition, nucleate boiling begins at surface temperature slightly above saturation (< 0.5 K) with no temperature excursion. The temperature excursions before initiating boiling on the 70 μm and 50 μm thick Cu nano-dendrites surface layers are small (3.7 K and 6 K), corresponding to surface temperatures of ∼ 55.1 °C and 57.4 °C, respectively. These temperatures are much lower than recommended (85 °C) for reliable operation of most silicon electronics and CPUs.

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