Dynamic performance of loop heat pipes for cooling of electronics

Abstract

With the performance improvement of electronics, the recent trends in electronic industry pose a big challenge on heat dissipation. Conventional methods, i.e. air cooling, may not be able to handle the fast increasing heat flux. Using heat pipes, which have numerous advantages such as high heat transfer coefficient, non-movable components, longer transport distance, and compact structures, emerges to be one competitive option for electronics cooling. Based on the node analysis method and the conservation of energy and mass, this work develops a mathematic model to simulate the operation of heat pipes. After it is validated against experimental data, it is further applied to evaluate the dynamic performance of using a heat pipe for electronics cooling. Results show that the operation temperature of evaporator ranges from 47.5°C to73.1°C, which implies that the heat pipe can effectively cool down the CPU at different running status. The charging ratio of working fluid is identified as a key parameter and exists an optimal value. When keeping the charging ratio constant, a larger evaporator area can achieve a lower operating temperature.