Numerical simulation of droplet microdroplet movement in a flat finned tube under vibration

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Journal of Vibration and Shock ›› 2024, Vol. 43 ›› Issue (8) : 155-161.

GUAN Weijuan1,CHEN Qinghua2,3,ZHANG Bin3,JI Jiadong3,WANG Jiangang3,4,LIU Ping3

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Abstract

In the flat finned tube heat exchanger working in low temperature and high humidity environment, frost phenomenon is easy to occur, resulting in increased energy consumption and failure rate. The vibration effect on the microdroplet at the initial stage of frost formation can accelerate the sliding process of the microdroplet and thus achieve the effect of frost formation. The growth process of microdroplet in the early stage of frosting was numerically simulated and analyzed, and the growth characteristics of microdroplet on different surfaces were obtained and verified by the literature values. Then, the effects of different vibration frequencies were studied by using the data of microdroplet at different times through numerical simulation, and finally an experimental platform was built for verification. The results show that for different surfaces, the larger the surface contact Angle is, the slower the growth rate of microdroplet is. The optimal vibration frequency corresponding to different volumes of microdroplets is different. When the volume of microdroplets is small, the higher vibration frequency makes the microdroplets oscillate back and forth on the wall surface of the base tube, which is not easy to slip off. When the volume of microdroplets is large, the higher vibration frequency is conducive to the microdroplets overcoming the wall friction and the droplet sliding off.

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Refrigeration system / Flat finned tube / Microdroplet growth / Vibration defrosting

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GUAN Weijuan1,CHEN Qinghua2,3,ZHANG Bin3,JI Jiadong3,WANG Jiangang3,4,LIU Ping3. Numerical simulation of droplet microdroplet movement in a flat finned tube under vibration[J]. Journal of Vibration and Shock, 2024, 43(8): 155-161

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