Numerical simulation of fine particles charging and collection in an electrostatic precipitator with regular barbed electrodes

摘要

The processes of charging and collection of fine particles (< a few |iin) in an electrostatic precipitator (ESP) are modelled taking into account the secondary gas flow induced by "barbed" ionizing electrodes. In particular, in configurations characterized by a rectangular lattice of ionizing point electrodes, the secondary flow in the form of axial rolls can be vigorous and the resultant gas flow inside the precipitator can be considered as axially invariant to a first approximation. A numerical simulation of charging, transport and collection of fine particles is presented, based on the approximation of a gas flow independent of the axial variable, The three-dimensional character of the distributions of electric field E and ionic space charge p which plays an important role in the charging of particles is taken into account. This allows simulating the particles trajectories and the dynamics of their charging. A statistical study shows that all particles of a given size do not get the same charge. The histograms of charge are presented and discussed. Finally the obtained mean particle charges are compared with theoretical predictions.