摘要
本文通过高速可视化方法与数字粒子图像测速技术,实验研究了电场调控剪切流场内液滴形变及旋转特征并阐明了其产生机理,讨论了电场及剪切流场独立和耦合作用时对液滴形变的影响规律。研究表明:单一剪切流场及单一电场均可以调控乳液形变,其形变程度由工质物性参数及剪切流场的毛细数和电场的电毛细数决定。当液滴相与连续相电导率比R大于介电常数比S时,电场力、剪切流场黏性力及表面电荷对流之间相互合作促进液滴变形。而当R小于S时,电场力与黏性力促进液滴变形,但是表面电荷对流效应将抑制液滴变形。此外,剪切流场中乳液内部形成涡流,当R>S及R<S时,电场分别增强和降低液滴内部涡流强度。
By employing the digital particle image velocimetry method,the electric-field-controlled deformation and rotation characteristics of a droplet in a shear flow field are experimentally studied.The electrohydrodynamic mechanisms of the droplet deformation are revealed and the effects of the electric field and shear flow field on the droplet deformation are summarized.It found that the droplet deformation can be controlled by altering the strengths of the shear flow field and electric field,and the physical parameters of the fluids.when the conductivity ratio of the droplet to the continuous fluid R is larger than the permittivity ratio S,the viscous force cooperates with the electric force and the surface charge convection effect to promote droplet deformation.when R<S,the electric force and the shear flow force promote the droplet deformation,while the surface charge convection effect reduces it.Besides,a vortex inside the droplet is formed by the shear flow.The vortex intensity is enhanced and reduced by the electric field when R>S and R<S,respectvly.
作者
郝冠球
刘向东
陈永平
HAO GuanqiuLIU Xiangdong;CHEN Yongping(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 210096,China;College of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225127,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2024年第1期129-134,共6页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.52036006)。
关键词
电场
剪切流场
电流体动力学
液滴形变
electric field
shear flow field
electrohydrodynamics
droplet deformation
