Session: 05-04 Phase change cooling technologies

Paper Number: 97459

97459 - Dielectric Liquid Thermal Management for Near-Junction Wide-Bandgap Power Electronics Cooling 

Silicon carbide (SiC) power devices are replacing standard silicon (Si) devices due to their superior thermal and electrical characteristics. These devices are typically significantly smaller in footprint, compared to Si based devices, resulting in higher heat fluxes. Dielectric coolants allow near-junction cooling, by eliminating the requirement of electrically and thermally insulating substrate layer in conventional power electronics packaging, allowing higher heat flux capabilities. Flow boiling in a microgap with pin-fins can deliver efficient and direct cooling. A new package design involving flow boiling of a dielectric coolant near-junction of the devices has been examined in this study. Single phase and boiling flows of HFE 7200 have been experimentally examined under device level heat fluxes of up to 1 kW/cm². The studied configuration involves flow boiling in a microgap 55 mm x 35 mm, and height 1 mm, with staggered pin-fins of diameter 0.5 mm and pitch 1 mm. Heat transfer measurements including heat transfer coefficient and transient pressure drop and high-speed flow visualizations have been performed for a range of heat fluxes (400 W/cm² - 1600 W/cm²). The thermal resistance of the heated footprint is presented as means of comparison to existing thermal management solutions.

Presenting Author: Akshith Narayanan Georgia Institute of Technology