Visualization and Behavior Analysis of Re-entrainment Particle in Electrostatic Precipitator

The reduction of the particulate matters (PMs) emitted from diesel engine exhaust attracts attention. For this problem, an electrostatic precipitator (ESP), one of the air purification systems has been developed. Diesel engine particles in ESP are detached from the collection plate where the electrostatic repulsion force due to induction charge exceeds particle adhesion force on the collection electrode. This phenomenon has been known as re-entrainment. Particle Image Velocimetry (PIV) is commonly used to analyze the ionic wind and particle behavior in ESP. PIV makes possible noncontact measurements. In this study, PIV was employed to visualize the particle behavior inside ESP, and explore changes in the characteristics, namely, the number of particles, particle velocity, and moving angle of particle for re-entrainment particles. In results, it was considered that the PIV method is suitable for the observation of the re-entrainment phenomena. Furthermore, a model of the force which acts on a particle is proposed, the effectiveness of the proposed force acting model was experimentally verified.