Serious ice accretion on insulators may cause icing flashover and lead to power-off accident of grid. Researches on the flow field and trajectories of water droplet impinging on insulator surface are of great significance to understanding the icing mechanism of insulator. We chose the aerodynamic insulator as study object. On the basis of the Lagrange method

we proposed an area-divided method of calculating droplet collision efficiency after solving the flow field and droplet trajectories around insulator. Furthermore

we experimentally investigated the effects of wind velocity and median volumetric diameter（MVD） of water droplet on water droplets impingement characteristics. It is found that there is no remarkable difference（less than 3%） between the collision efficiency on

the steel cap and shed edge of aerodynamic insulator. The collision efficiency on these two areas is far higher（60%

1

90%） than that of windward surface. The droplet collision efficiency on windward surface is almost twice as that on leeward surface of insulator. The collision efficiency increases with the increase of wind velocity and MVD

and the influencing degree of MVD on droplet collision efficiency is more remarkable than that of wind velocity. The insulator icing characteristics by analysis with area-divided method is more consistent with that from the experimental results.