TURBULENT PARTICLE DISPERSION IN AN ELECTROSTATIC PRECIPITATOR

The behaviour of charged particles in turbulent gas flow in electrosta tic precipitators (ESPs) is crucial information to optimise precipitat or efficiency. This paper describes a strongly coupled calculation pro cedure for the rigorous computation of particle dynamics during ESP ta king into account the statistical particle size distribution. The turb ulent gas flow and the particle motion under electrostatic forces are calculated by using the commercial computational fluid dynamics (CFD) package FLUENT linked to a finite volume solver for the electric field and ion charge. Particle charge is determined from both local electri cal conditions and the cell residence time which the particle has expe rienced through its path. Particle charge density and the particle vel ocity are averaged in a control volume to use Lagrangian information o f the particle motion in calculating the gas and electric fields. The turbulent particulate transport and the effects of particulate space c harge on the electrical current flow are investigated. The calculated results for poly-dispersed particles are compared with those for mono- dispersed particles, and significant differences are demonstrated. (C) 1998 Elsevier Science Inc. All rights reserved.