Coupling effects of the flow and electric fields in electrostatic precipitators

Abstract

In this study the variations of the velocity and electric fields in electrohydrodynamic (EHD) flows in a positive single-wire electrostatic precipitator are studied. The fully coupled systems of electrical and hydrodynamical governing equations are solved for both laminar and turbulent flow conditions. Particular attention is given to the flow-electric field coupling effects and the variation of the electrical potential and charge distribution induced by the gas flow field. The presented results show that the effects of airflow on electrical potential and charge density become noticeable at high cross-flow velocities. The electrical conditions in an electrostatic precipitator that was used in an earlier experimental study are also simulated. It is shown that the computational model predictions are in good agreement with the experimental data. A series of parametric studies for a range of parameters for the EHD flows in the single-wire precipitator are performed and the corresponding flow and electric fields are presented. An example of extension of the model to multiwire precipitator is also presented.