Experimental study on the electrohydrodynamic deformation of droplets in a combined DC electric field and shear flow field  

作　　者：Xiangdong Liu Guanqiu Hao Bo Li Yongping Chen 

机构地区：[1]Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 210096,China [2]School of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225009,China [3]Laser Fusion Research Center,China Academy of Engineering Physics,Mianyang 621900,China

出　　处：《Fundamental Research》2023年第2期274-287,共14页自然科学基础研究（英文版）

基　　金：supported by the National Natural Science Foundation of China (51725602 and 52036006).

摘　　要：A visualization experiment was conducted to investigate the electrohydrodynamic deformation of droplets in a combined DC electric field and shear flow field.Detailed experimental data on both the transient and steady droplet deformation parameters(D)and orientations(ϕ_(d))are provided at R>S and R<S(R:conductivity ratio;S:permittivity ratio)under different electric field and shear flow field combinations.The internal flow characteristics of the deformed droplet were also examined via the digital particle image velocimetry(DPIV)method.Due to the competition of the extensional component(EC)and the rotational component(RC)of these two fields on the droplet,the response ofϕ_(d) is faster than that of D when an electric field is combined with a shear flow.Additionally,under the competition of the EC and RC at R>S and R<S,the steady-state D andϕ_(d) values exhibit distinct variations.In particular,surface charge convection plays a non-negligible role in enhancing and reducing droplet deformation at R>S and R<S,respectively.In addition,an asymmetric vortex forms inside the deformed droplet in the combined fields,and its velocity is lower under R>S and higher under R<S than in pure shear flow.The available prediction models use the experimental data to predict D,and a modified prediction model is proposed for improving the prediction accuracy ofϕ_(d).

关 键 词：Droplet deformation ELECTROHYDRODYNAMICS Electric field Shear flow Prediction model 

分 类 号：TM33[电气工程—电机]