Numerical Simulation of the Physical Process of Collision between Wet Snow Particle and Insulator Surface under DC Electric Field

A new type of the insulator named integrated lightning protection insulator incorporates insulation function of the insulator and lightning protection function of the arrester. Due to the particularity of the structure, the electric field and flow field characteristics of the lightning protection insulator with DC are bound to be different from common composite insulator in a snowfall environment. Therefore, based on the field charging theory, the influences of electric field force, gravity and air drag force on wet snow particles were taken into account. The movement characteristics of particles near the surface of two types of the insulators were analyzed and compared through multi-physics coupling simulation and the effect of DC electric field on the trajectories of wet snow particles around the two was revealed. The results show that wet snow particles are more likely to collide with the insulator surface under DC electric field, especially for locations with a high electric field strength. As the wind speed and particle diameter increase, the influence of the electric field is weakened, and the movement of particles tends to the upper and lower surfaces of the insulator. Numerical simulation reveled that the change in the movement direction and speed of wet snow particles caused by DC electric field is the primary cause of the intensification of snow accretion on the insulator.