The study of nanodroplets coalescence is crucial for the development of nanofluid technology and crude oil dehydration. The coalescence behavior of multiple nanodroplets in single electric field, single swirl centrifugal field, and the coupling of electric field and swirl centrifugal field (E&SC coupling fields) was investigated using the molecular dynamics (MD) method. The validation work verified the feasibility of the present MD models. The effects of electric field frequency (f) and strength (E), angular velocity (omega), water content (wt), and component types on the coalescence behavior of multiple nanodroplets were comprehensively investigated. The results show that direct current (DC) field was more suitable for dealing with low wt emulsions, while alternating current (AC) field was more suitable for dealing with high wt emulsions. The swirl centrifugal field with low (high) omega was correspondingly suitable for dealing with low (high) wt emulsions. The coalescence efficiency increased with increasing Re (20-160) and f (0-40GHz). In addition, not only the large-sized droplets were easy to be formed, but also the small-sized droplets were easy to be removed in the E&SC coupling fields, which can enhance the coalescence efficiency between multiple nanodroplets. The critical Ca-E of AC&SC coupling fields was improved 18% than DC&SC coupling fields. Finally, the presence of Span-80 (SPAN) molecules increased the coalescence efficiency of multiple nanodroplets and raised the critical Ca-E to 0.11. The results of this paper can be potentially helpful for the development of high-efficiency electric dehydration technology at microscale.

采用电化学试验,静态腐蚀浸泡试验,扫描电镜观察等研究了B44660超级铁素体不锈钢和316L不锈钢材料在模拟中国中部地区地热水环境中的腐蚀和结垢行为.结果 表明:在此类地热水环境中,两种不锈钢的腐蚀速率均随温度的升高而增加;且两种不锈钢在低温地热水环境中均存在结垢现象,垢层的主要成分均为CaCO和MgCO3;316L不锈钢的耐腐蚀与阻垢性均优于B44660不锈钢的,更适合应用于地热环境中.