A review on ultrasound-enhanced heat transfer

This review comprehensively examines recent advances in ultrasound-enhanced heat transfer, a promising active cooling technology for high-heat-flux electronic devices. It systematically analyzes the fundamental mechanisms: thermal effect, acoustic cavitation, acoustic streaming, acoustic fountain and atomization. Among them, acoustic cavitation and acoustic streaming are identified as the two primary mechanisms for enhancing heat transfer. In addition, the review discusses their roles in improving heat transfer in single-phase flow, pool boiling, forced convective boiling, and heat exchanger. Key influencing parameters, such as ultrasonic frequency, power, transducer configuration, flow rate, heat flux, and subcooling are critically evaluated. The synergistic effects of combining ultrasound with nanofluids, channel structure, and other active methods are also highlighted. Numerical modeling approaches, including bubble dynamics and multiphysics simulations, are reviewed for their potential in exploring underlying mechanisms and optimizing system performance. Finally, current challenges and future research directions are outlined, with a focus on multiscale coupling, energy efficiency, and adaptability under extreme conditions.