Discrete-element method for particle capture by a body in an electrostatic field

作者：Liu G; Marshall J S^*; Li S Q; Yao Q

来源：International Journal for Numerical Methods in Engineering, 2010, 84(13): 1589-1612.

DOI：10.1002/nme.2953

• discrete-element method
• dielectrophoretic force
• boundary-element method
• electrostatic field

A discrete-element method is developed for applications involving interaction of spherical particles with a body of arbitrary shape in an electrostatic field. The electric field is induced both by charged particles and by other ';macroscopic'; bodies (e.g. electrodes). The electric field due to macroscopic bodies is computed using a boundary-element method that accounts for the particle influence. An algorithm using approximate particle images is introduced to improve electric field resolution for particles lying close to the body surface. The long-range electric field induced by particles is computed using an optimized, adaptive multipole expansion method. The method is applied to the formation of chain-like particle aggregates, with long-range particle attraction governed by the electric field and particle adhesion by van der Waals forces. The method is illustrated by simulation of the capture of uncharged particles on a cylindrical electrode. A local panel subdivision method is developed to mitigate particle drift toward panel edges induced by panel discretization errors. The particle deposition pattern at different cylinder surface charge levels is studied, which shows that long straight particle chains are formed under strong electric fields. The predicted particle capture efficiency agrees well with the experimental data.

• 出版日期2010-12-24
• 单位清华大学