Visualization Method of Boiling Bubble Behavior for Boiling Heat Transfer Improvement

Abstract

Heat generation of computer chips for autonomous driving level 4 and 5 will be much higher than the current market level. In order to solve this cooling issue, we have developed an immersion boiling cooling system working under atmospheric pressure. This system enables high cooling performance by mounting a boiling plate on the heating chips. Moreover, the atmospheric pressure system realizes easy installation in the vehicle and cost reduction. In order to improve the cooling performance, a method to quantify the nucleation site by visualization was developed. Using this method, the number of nucleation site and the thermal conductance were found to be approximately proportional.