Nucleation and Critical Heat Flux in Spray Cooling

点击翻译按钮获取中文摘要

ABSTRACT Proposal Number: CTS 9813595 Principal Investigator: L. Chow, R-H Chen This award is to investigate the fundamental processes involved in spray cooling. In a previous study, the PIs developed a semi-transparent synthetic-diamond heater which could produce critical heat fluxes in water and FC-72. With this heater, bubble histories could be recorded on video. The proposed work will clarify the effects of nucleation, secondary nucleation, and premature bubble removal by impinging spray droplets on the heat transfer and the critical heat flux. This will be done by measuring bubble growth rate, bubble size, and bubble population across the heater surface using the video imaging system. The study will correlate nucleation with the spray characteristics of mass flow rate, droplet size and number density. Estimations of the relative significance of surface and secondary nucleation will improve the understanding of the spray process and provide benchmark data for future work.