Abstract This paper presents experimental and numerical studies of heat transfer enhancement of water in an annulus under ultrasonic waves and fluid flow. An experimental setup is designed and built from two concentric pipes and a bolted Langevin ultrasonic transducer with a frequency of 25.7 kHz stuck to the inner pipe. Two new solvers are developed in OpenFOAM software and a numerical simulation is carried out to model the effect of both acoustic streaming and fluid flow on heat transfer and flow field. There are good agreements between the experimental and numerical results. Experimental results show that increasing the Reynolds number decreases the effect of acoustic streaming as compared to the effect of fluid flow on heat transfer and flow field. As a result, heat transfer enhances about 87% and 25% for Reynolds numbers of 32 and 674, respectively, at the transmitted acoustic power of 100 W. Numerical simulation is used to find the reason of heat transfer enhancement under ultrasonic waves, and results show that the cross-flow generated by circulations due to acoustic streaming is responsible for heat transfer augmentation.

中文翻译：

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超声场下环空传热增强：数值和实验研究

摘要 本文介绍了超声波和流体流动作用下环空中水传热增强的实验和数值研究。实验装置是由两个同心管和一个固定在内管上的频率为 25.7 kHz 的螺栓连接的朗之万超声波换能器设计和建造的。在 OpenFOAM 软件中开发了两个新的求解器，并进行了数值模拟，以模拟声流和流体流动对传热和流场的影响。实验和数值结果之间有很好的一致性。实验结果表明，与流体流动对传热和流场的影响相比，增加雷诺数会降低声流的影响。结果，当雷诺数为 32 和 674 时，传热提高了约 87% 和 25%，