CFD Simulation of Electrostatic Precipitators and Fabric Filters State of the Art and Applications

Abstract

This paper clearly discloses the possibilities, which the numeric flow simulation offers in case of modelling the two-phase flow in electrostatic precipitators and fabric filters with view to design new and retrofitting of old plants today. Contrary to physical flow models the CFD simulation is capable to consider high dust loads and the distribution of dust in the gas flow. This is an advantage which will lead to the displacement of the physical flow models by sophisticated CFD simulations while investigating the two phase flow in dust precipitators. This paper explains the main features of the used CFD models for the detailed simulation of these types of precipitators. Both CFD model approaches are based on an Euler-Lagrange formulation of the two-phase flow consisting of gas and solid particles. Also the paper points out, how important a highly detailed geometry model is for a strong simulation and reliable results. So all the ducts up- and downstream the precipitator itself including every inner part (e.g. guide vanes, dampers, etc.) are integrated in the CFD geometry model. The simulations show that today reliable CFD simulations of both precipitator types the electrostatic and the fabric filter in consideration of the phase interaction between gas and solid particles including separation are possible with high accuracy. Thus it is possible to examine special questions such as optimization of gas flow, reduction of pressure loss or the increase in separation efficiency, purposefully tailored to a precipitator, fast and economically.