Excessive electric field strength causes the droplets to contact but not coalesce, severely deteriorating the oil–water separation efficiency. The investigation of the non‐coalescence of nonidentical droplets in oil under a DC electric field is conducted using high‐speed photography. The effects of droplet volume ratio and interfacial tension ratio on the characteristics and critical parameters for droplet non‐coalescence are systematically explored. The results show the critical electrocapillary number for the non‐coalescence of nonidentical droplets and critical contact cone angle decreases as the volume sum increases or the interfacial tension ratio decreases, which is related to the competition between the resultant electric field force and the interfacial tension force. These results contribute to optimizing the operating parameters of the electric coalescer and improving the oil–water separation efficiency.

中文翻译：

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直流电场下油中不同液滴的不聚结

电场强度过大会导致液滴接触但不会聚结，严重降低油水分离效率。使用高速摄影对直流电场下油中不同液滴的不聚结进行了研究。系统探讨了液滴体积比和界面张力比对液滴不聚结特性和关键参数的影响。结果表明，不同液滴不聚结的临界电毛细管数和临界接触锥角随着体积和的增加或界面张力比的减小而减小，这与合成电场力和界面张力之间的竞争有关。这些结果有助于优化电聚结器的运行参数，提高油水分离效率。