A heat exchanger based on the piezoelectric pump for CPU cooling

To satisfy the cooling demands required by the highly integrated electronic devices, a heat exchanger integrated with a ball valve piezoelectric pump and a multi-stage Y-shaped micro-channel heat sink was proposed and demonstrated. The effects among the flow rate, back pressure of the piezoelectric pump, and the driving frequency of the heat exchanger were investigated to assess the driving performance. Subsequently, the piezoelectric heat exchanger was used to cool the CPU of commercial computers, and the performance of the heat exchanger was discussed under different thermal power consumption. The results showed that the temperature of the CPU under extreme thermal load was controlled by the heat exchanger within 55 ℃. The relationship between heat resistance and convection heat transfer coefficient was also analyzed. When the CPU was operating at 30 W, the heat sink owned the smallest thermal resistance and the largest heat transfer coefficient. From the conclusion of the comparative tests, the heat exchange speed and heat exchange effect of the piezoelectric heat exchanger were obviously better than the original air cooling system of the computer. The proposed heat exchanger may contribute in the field of the heat exchange of electronic devices in near future due to its certain performances.