Numerical simulation of the flow and the collection mechanisms inside a laboratory scale electrostatic precipitator

Various methods and techniques are being used currently in order to improve the cleaning efficiency of electrostatic precipitators (EP). These techniques have been developed on the basis of past experience, measurements and performance data of industrial and laboratory scale units. The aim of this paper is to present a simulation method that can be used to give insight to the collection mechanisms and phenomena that take place inside electrostatic precipitators. The effects of the electrostatic forces on the particle and gas phases are taken into account. Emphasis is given to the impact of the ionic wind on the gas flow and its influence on the particle transverse transport velocities. The numerical results show the development of cross stream vortices due to ionic wind, with their magnitude depending on the applied wire-to-plate voltage. The vortices affect the collection efficiency of the EP, particularly, in the case of small size particles. Flow uniformity from plate to plate leads to increased collection efficiency of the EP.