To considerate the harmness and the icing type of the power transmission line

the glaze was the most deadly harmness to the power transmission line than the other icing types. Dynamic characteristics of droplets impacting on the solid surface has a significant effect on the mechanism of heat and mass transfer during the phase transformation as well as the mechanism of the conductor ice coating. The evolution behaviors of droplets impacting on the different temperature curved surfaces were investigated by the visional experiments. It showed that the effects of the different undercooling degree and the surface curvature on the law of droplet spreading behavior. The results indicated that the circumferential liquid film spread out better and the axial one did worse with the increase of cylindrical surface curvature. Increasing the surface undercooling degree

the droplet spread worse and oscillation time became shorter and the upper film freeze faster on the undercooling surface. However

the droplet impacting on undercooling surface spread better than that at ambient temperature. It was speculated that there was an ice film formed rapidly at the bottom of the droplet when it spread on the cold solid surface by analyzing the effects of the surface tension and viscosity of water droplet on the spread behavior. The ice film

which obviously altered the interface energy between the solid phase and liquid phase

made the droplet spread easily. The ice film was distinctly observed at the droplet recoiling stage. The conclusion can provide theoretical reference for glaze ice on the conductors.