The prevention and control of icing flashover on transmission line insulators has always been a key task in power grid ice disaster prevention and mitigation. Optimizing the shed structure of composite insulators to reduce the icing rate is one of the effective anti-icing methods. Based on the fundamental theory of fluid mechanics

this paper derives a formula for calculating the spacing of water droplets based on parameters such as the liquid water content in the air and the median volume diameter of droplets. By batch-emitting and tracking the trajectories of water droplets out of composite insulators during the icing process

the distribution and collision efficiency of water droplets on the insulator sheds are obtained. By taking a single shed of a composite insulator as the research object

the influence of different environmental and structural parameters on the collision of water droplets is numerically analyzed

and natural icing verification tests are conducted. The results show that the key structural parameters affecting the capture rate of supercooled water droplets by composite insulators during icing are the shed diameter and the upper and lower inclination angles

while the key environmental parameters are wind speed and the median volume diameter of water droplets. The smaller the shed diameter of the composite insulator is

the greater the overall water droplet collision coefficient α1 will be. Sheds with smaller upper inclination angles are more prone to icing; however

under severe icing conditions

smaller upper inclination angles are more beneficial for reducing the water droplet capture efficiency and icing rate. Under natural icing conditions

composite insulator sheds with smaller upper inclination angles have a lower icing rate compared to those with larger upper inclination angles. The smaller the shed diameter is

the less the icing mass is

but the more easily the shed is bridged by ice. The conclusions of this paper provide technical references for the optimization and design of anti-icing structures for composite insulator sheds.