Statistical characteristics and mechanism analysis of adhered particle on surface under strong electric field
Yunpeng Jianga, Lee Lia,*, Ming Lub, Rumeng Wanga, Yiwen Jianga, Shanfeng Liub, Chao Suc
Insulators on high-voltage transmission lines are almost the only man-made structures on the Earth’s surface intended for long-term operation under strong electric fields. After samples of natural contaminant particles were collected from insulator surfaces in China, it was found that the particle diameter distribution (PDD) was mainly concentrated in the 5–50 μm range. To analyze the statistical characteristics of these particles, this work studies the physical processes of particle collision and adhesion using the theories of hydrodynamics and collision dynamics. The physical model considers coupling of the fluid field and the electric field, introduces an adhesion criterion, and establishes a particle and surface collision model. The effects of relative humidity, wind speed, aerodynamic shape, electric field type, and electric field strength on particle adhesion were analyzed. The results show that the relative humidity and wind speed have very significant effects and the influences of the electric field type and the electric field strength are obvious, but the influence of the aerodynamic shape is relatively weak. The simulation results support the statistical characteristics determined in this work. The physical model established here provides reference values for study of the adhesion characteristics of particles on surfaces under electric fields.
Contaminant particle; Collision; Adhesion; Particle diameter; Simulation analysis