脉冲电场作用下流场对油中液滴的影响分析  

Effect of flow field on droplets in oil under pulsed electric field

作　　者：许凯 袁蒙 XU Kai;YUAN Meng(China Coal Technology Engineering Group Chongqing Research Institute,Chongqing 400700,China;School of Chemical Engineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]中煤科工集团重庆研究院有限公司,重庆400700 [2]重庆理工大学化学化工学院,重庆400054

出　　处：《重庆理工大学学报（自然科学）》2024年第11期221-227,共7页Journal of Chongqing University of Technology：Natural Science

基　　金：重庆市自然科学基金重点项目(CSTB2023NSCQ-LZX0096)。

摘　　要：为探究在脉冲电场作用下流场对液滴运动的影响机制,采用有限元方法建立了油中液滴数值计算模型,并通过相场法捕捉液滴界面的动态变化,分析了流场对液滴变形和聚结的影响规律。研究发现:在脉冲电场作用下液滴的伸缩变形振动会带动周围油液形成环流,环流方向与液滴变形方向一致,对液滴变形起到促进作用,而在液滴变形状态发生改变的初期会同时存在与液滴变形方向相反的外部环流,对液滴变形起到短暂的抑制作用;流场对液滴聚结的影响与两液滴之间的距离相关,当两液滴相距较远时,流场对液滴聚结过程的影响极小,而当两液滴足够靠近时,液滴外侧的环流会促进液滴相互靠近,进而发生聚结。研究结果可为脉冲电场破乳机理的深入研究提供参考。To explore the influence of flow field on droplet movement under the action of pulsed electric field,this paper builds a numerical calculation model of droplet in oil by using finite element method.The dynamic change of droplet interface is captured by phase field method,and the influence of flow field on droplet deformation and coalescence is analyzed.We find that under the action of the pulse electric field,the stretching deformation vibration of the droplet will drive the surrounding oil to form a circulation,and the circulation direction is consistent with the deformation direction of the droplet,which plays a role in promoting the deformation of the droplet.At the initial stage of the change of the deformation state of the droplet,there will be an external circulation opposite to the direction of the droplet deformation,which plays a temporary role in suppressing the deformation of the droplet.The influence of flow field on droplet coalescence is related to the distance between two droplets.When two droplets are far apart,the influence of flow field on droplet coalescence is minimal.When two droplets are close enough,the circulation outside the droplets will enable the droplets to approach each other,and then coalesce.Our results provide the theoretical support for the further study of the mechanism of pulsed electric field demulsification.

关 键 词：脉冲电场 流场 液滴聚结 液滴变形 动态变化 伸缩变形振动 

分 类 号：TE624[石油与天然气工程—油气加工工程]