A High Flow Rate Piezoelectric Micropump for Miniature Liquid Cooling System

With the development of semiconductors, the heat generation of high-performance electronics increases rapidly. Liquid cooling technologies are considered promising options for high-performance electronics with the advantages of high thermal performance, efficiency, and flexibility. To meet the requirements of miniature liquid cooling systems, micropumps with high performance and small volume are highly desirable. Piezoelectric micropump shows simple structure, large power density, and high working efficiency, which has the potential to meet the requirements of high hydraulic performance and miniaturization at the same time. Due to the characteristics of the piezoelectric actuator, the flow rates of piezoelectric micropumps are still not big enough for high-performance liquid cooling systems. In this study, we developed a high flow rate piezoelectric micropump by utilizing low-frequency resonance amplification. The piezoelectric actuator and the working fluid were designed as a low-frequency resonant system. The piezoelectric micropump achieves a maximum hydraulic performance of 546 mL/min and 31.6 kPa with an oversize of 40 mm × 40 mm × 15 mm, which shows one of the best performances at similar sizes in the literature. Then, the piezoelectric pump was applied to a jet impingement liquid cooling system and dissipated a heat load of 200 W (50 W/cm²) with a chip temperature rise below 35 °C.