Estimation of droplet charge forming out of an electrified ligament in the presence of a uniform electric field

Electrostatics 2015

物理学;数学

Osman, H.^1 ; Castle, G.S.P.^1 ; Adamiak, K.^1 ; Fan, H.T.^2 ; Simmer, J.^2

Department of Electrical and Computer Engineering, Western University, London

ON, Canada^1

General Motors Global, Warren

MI, United States^2

关键词: 2d axisymmetric models;    Different boundary condition;    Electric field intensities;    Electrostatic application;    Electrostatic painting;    High voltage electrodes;    Liquid conductivity;    Uniform electric fields;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/646/1/012006/pdf
DOI  :  10.1088/1742-6596/646/1/012006

来源: IOP

【 摘 要 】

The charge on a liquid droplet is a critical parameter that needs to be determined to accurately predict the behaviour of the droplet in many electrostatic applications, for example, electrostatic painting and ink-jet printing. The charge depends on many factors, such as the liquid conductivity, droplet and ligament radii, ligament length, droplet shape, electric field intensity, space charge, the presence of adjacent ligaments and previously formed droplets. In this paper, a 2D axisymmetric model is presented which can be used to predict the electric charge on a conductive spherical droplet ejected from a single ligament directly supplied with high voltage. It was found that the droplet charging levels for the case of isolated electrified ligaments are as much as 60 times higher than that in the case of ligaments connected to a planar high voltage electrode. It is suggested that practical atomization systems lie somewhere between these two extremes and that a better model was achieved by developing a 3D approximation of a linear array of ligaments connected to an electrode having variable width. The effect on droplet charge and its radius was estimated for several cases of different boundary conditions.