Force-fed evaporation and condensation utilizing advanced micro-structured surfaces and micro-channels

This paper presents results of an experimental study on phase change cooling of high flux electronics utilizing an innovative phase-change technique involving force-fed evaporation and condensation. The technique utilizes high-performance micro-structured surfaces consisting of alternating fins and channels, coupled with a force-fed mechanism in the evaporator and condenser. The force-fed mechanism provides a highly vigorous micro-channel convective heat transfer environment with the net effect of substantially higher heat transfer coefficients without the high-pressure drop penalties that are normally associated with such flows. Our recent results demonstrate dissipation heat flux levels well above 300 W/cm2 with corresponding heat transfer coefficients of close to 90,000–100,000 W/m2 K, using HFE-7100 as the working fluid. For the condensation mode, the force-fed method produces heat fluxes up to 58 W/cm2 with a heat transfer coefficient of 32,000 W/m2 K using HFE-7100.