Evaluation of Particle Mass Transfer Rates in Electrostatic Precipitators

Abstract

Particle deposition (mass transfer) modeling within electrostatic precipitators (ESPs) requires numerical solutions for fluid flow, electrostatic potential, and particle charging and migration. To better facilitate predictions of ESP performance, we introduce a theoretical framework relying on the determination of the cumulative particle deposition distribution function (CDDF) to calculate mass transfer coefficients. Implementing this approach with a recently-developed electrohydrodynamic flow solver and particle trajectory simulations, we analyze particle penetration and charging rates in a wire-plate ESP, obtaining excellent agreement with experimental data. We also compare to analytical CDDF models in two ideal limits: the well-mixed limit (exponentially distributed) and the ballistic limit (Heaviside functions). We find true CDDFs are not simply explained by these analytical approaches and are highly initial position- and particle diameter-dependent. However, once determined, CDDFs can be used to explore the effects in inlet concentration profile and ESP length without the need for additional simulations.