交流电场中水滴破裂及其影响因素研究

Investigation on Water Droplet Rupture and the Influencing Factors in High-Voltage AC Electric Field

本文采用白油和水为实验介质,利用显微高速摄像系统对高压交流电场中油中水滴破裂的临界参数及其影响因素进行了研究.结果表明:蒸馏水和含有表面活性剂水滴的破裂临界电场强度和(1/dd)^(1/2)。呈正比关系,并且界面张力越低、液滴直径越大,临界场强越小;频率对临界电场强度没有影响;不同矿化度水滴的临界电场强度随液滴粒径增大而减小,且普遍小于蒸馏水滴的临界电场强度;椭球液滴的离心率约在0.827~0.856之间时,液滴开始失稳破裂,此时其长短轴之比约为1.78~1.94。

Experiments were carried out to investigate the critical parameters of droplet rupture and its influencing factors in oil under high voltage AC electric field with different types of white oil and water. With a micro high-speed camera system and image processing technology, the rupture of droplet was observed and analyzed. The results indicate that the critical electric field strength of droplet rupture is proportional to （1/dd）1/2 for both distilled water and water containing surfactant. The critical electric field strength is smaller when interfacial tension is smaller and droplet diameter is larger. The frequency of electric field does not influence the critical electric field strength. The critical electric field strength also decreases with the increase of droplet diameter when water containing NaC1, which is smaller than that of distilled water droplet. The critical eccentricity before rupture is t in the range from 0.827 to 0.856, corresponding to axial ratio from 1.78 to 1.94.