NUMERICAL COMPUTATION OF CORONA SPACE-CHARGE AND V-I CHARACTERISTIC IN DC ELECTROSTATIC PRECIPITATORS

A procedure is presented for the numerical computation of the corona space-charge density and V-I characteristic in dc electrostatic precipitators in the absence of fly ash. An iterative numerical procedure, based on the finite element method, is implemented for solving Poisson's and continuity equations satisfying Kaptzov's assumption on the coronating conductors. The mathematical model is applied to a duct of an electrostatic precipitator; the ion charge density, electric potential, and electric field distributions are computed. The V-I characteristic, obtained by means of the proposed procedure, is compared with the experimental one measured by the Italian Electricity Authority (Enel) in a pilot precipitator put in the slipstream of the flue gas duct of a 35-MWe coal boiler. The agreement between computed and experimental values shows the efficiency of the numerical procedure.