Affiliations: Center of Plasma and Laser Engineering, Institute of
Fluid Flow Machinery, Polish Academy G of Sciences, 80-231 Gdańsk,
Fiszera 14, Poland, E-mail: [email protected] | Department of Electrical and Electronic Engineering,
Oita University, 700 Dannoharu, Oita 870-1192, Japan
Abstract: Although improving electrostatic precipitator (ESP) collection of
fine particles (micron and submicron sizes) remains of interest, it is not yet
clear whether the turbulent flow patterns caused by the presence of electric
field and charge in ESPs advance or deteriorate fine particle precipitation
process. In this paper, results of the laser flow visualization and Particle
Image Velocimetry (PIV) measurements of the particle flow velocity fields in a
wire-to-plate type ESP model with seven wire electrodes are
presented. Both experiments were carried out for negative and positive polarity
of the wire electrodes. The laser flow visualization and PIV measurements
clearly confirmed formation of the secondary flow (velocity of several tens of
cm/s) in the ESP model, which interacts with the primary flow. The particle
flow pattern changes caused by the strong interaction between the primary and
secondary flows are more pronounced for higher operating voltages (higher
electrohydrodynamic number NEHD) and lower primary flow velocities (lower
Reynolds number Re). The particle flow patterns for the positive voltage
polarity of the wire electrodes are more stable and regular than those for the
negative voltage polarity due to the nonuniformity of the negative corona along
the wire electrodes (tufts).
