Electronic cooling via acoustic-enabled low-power compact heat exchanger

Contactless acoustics provide a unique, flexible active means for phase-change heat transfer enhancement. However, the ultrasonic transducers used for conventional acoustic enhancement are bulky and unfavorable for integration, and the heat accumulation under high power is not conducive to long-term operation, with limited enhancement in the critical heat flux (CHF). Herein, an acoustic-enabled low-power compact heat exchanger (ALCHE) is proposed with low energy consumption and long operation duration. Based on image processing and bubble tracking algorithm, it is found that the acoustic field accelerates bubble detachment and migration for achieving superior heat flux and larger heat transfer coefficient (HTC). 1.5 kHz acoustic field performs better heat transfer performance due to its strong acoustic radiation force magnitude and excellent acoustic pressure field direction. The stronger acoustic radiation force from higher acoustic power promotes the heat transfer performance among different acoustic powers. Long-time stable operation of acoustic field enhanced heat transfer under high heat flux is achieved with low acoustic power. Our designed heat exchanger not only overcomes the limitation of traditional bulky transducers, but also provides insights into the acoustic-enabled flow boiling heat transfer process. Improving the cooling performance of high-power electronics in confined spaces remains a challenge. Herein, the authors propose an acoustic-enabled low-power compact heat exchanger that utilizes contactless acoustics as a flexible active means for enhancing phase change cooling.