Pool Boiling Cooling using Aqueous Surfactant Solutions for High Heat Generating Devices

Abstract

Pool boiling cooling performance of the high heat generating devices is examined experimentally. Influence of aqueous surfactant solutions on the subcooled boiling heat transfer at the surface of dummy CPU is investigated. Surfactants used are sodium myristate, potassium stearate, and potassium oleate. Addition of surfactant to pure water is able to enhance the nucleate boiling. When sodium myristate is used as surfactant, improvement of heat transfer coefficient is particularly large and is about two times of pure water at equal heat flux condition. Boiling heat transfer is improved greatly at the surfactant concentration of 0.01 wt% ~ 0.1 wt% which meets the critical micelle concentration of the surfactants. The effect of heat transfer surface direction on cooling performance of surfactant solutions seems to depend on the bubble size after departure. For potassium stearate solution which has rather large bubble size after departure, improvement of heat flux for vertical type is particularly large and is about twice of horizontal case.