Jumping-droplet electronics hot-spot cooling

TLDR: In this article, a jumping-droplet-based electric-field-enhanced (EFE) condensation method was proposed to achieve active hot spot cooling in electronic devices.

Abstract: Demand for enhanced cooling technologies within various commercial and consumer applications has increased in recent decades due to electronic devices becoming more energy dense. This study demonstrates jumping-droplet based electric-field-enhanced (EFE) condensation as a potential method to achieve active hot spot cooling in electronic devices. To test the viability of EFE condensation, we developed an experimental setup to remove heat via droplet evaporation from single and multiple high power gallium nitride (GaN) transistors acting as local hot spots (4.6 mm × 2.6 mm). An externally powered circuit was developed to direct jumping droplets from a copper oxide (CuO) nanostructured superhydrophobic surface to the transistor hot spots by applying electric fields between the condensing surface and the transistor. Heat transfer measurements were performed in ambient air (22–25 °C air temperature, 20%–45% relative humidity) to determine the effect of gap spacing (2–4 mm), electric field (50–250 V/cm) and app...