Experimental and numerical study on thermal performance of Wood's alloy/expanded graphite composite phase change material for temperature control of electronic devices

摘要

The current investigation focuses on the feasibility of effectively managing the thermal conditions of electronic devices using Wood's alloy/expanded graphite composite phase change material (PCM). A thermal management system integrated with the composite PCM-based substrate is constructed and the thermal behaviors of this composite PCM under different testing conditions are studied through both experimental and numerical ways. The results indicate that the thermal performances of the composite PCM are dependent on input power density of the electronic chip, heat storage density and thermal conductivity of the PCM, and thickness of the PCM-based substrate. The temperature holding capability of the PCM can be obtained under high input power density. Under low input power density, the substrate only behaves as a heat spreader. Enhancing the heat storage density of the composite PCM is advantageous to obtain longer critical time (the required time for the chip to reach a critical temperature). Also, varying the thermal conductivity of the PCM from 14.9 to 59.6?W?m?1?K?1leads to slight changes to the PCM's temperature control performance during the chip's working period under natural cooling conditions, whereas extending the thickness of the substrate can both lower the chip's equilibrium temperature and prolong the critical time.