A NOVEL MICRO COOLING SYSTEM FOR ELECTRONIC DEVICE BY USING MICRO CAPILLARY GROOVE EVAPORATOR

摘要

In the presented study, a novel micro cooling system for electronic device by using a micro capillary groove evaporator was proposed. Based on experimental data in open condition (atmospheric condition), it was found that liquid level has an obvious influence on evaporating heat flux. For a given liquid level, there exists an optimum groove size, which maximizes evaporation heat transfer capacity. The experimental results also indicated that the existence of transverse grooves enhances wall heat transfer for lower heat fluxes. By using the optimum groove sizes in open condition, we designed two types of closed cooling systems for personal computer's CPU chips: one is for desktop-type and the other is for notebook-type. Their cooling performances to keep the temperature of CPU chip below 90℃ reached 3.35x10~5W/m~2 and 2.51x10~5W/m~2, respectively for the desktop-type by using ethanol and the notebook-type by using methanol. Experimental results showed that the maximum cooling capacities of them strongly depend on the condensation capacities of condensers in the closed cooling system and the volume fraction of working liquid in the evaporator.