An approximate expression for the coagulation coefficient of bipolarly charged particles in an alternating electric field

Based on the kinetic equation of particles, an approximate expression is proposed for the coagulation coefficient of bipolarly charged particles with the effect of an alternating-current (AC) electric field. When the external electric field is high enough, the proposed solution agrees well with the previous numerical results of Koizumi, Kawamura, Tochikubo and Watanabe [2000. Estimation of the coagulation coefficient of bipolar-charged aerosol particles. Journal of Electrostatics, 48, 93–101.].