Influence of torsion on icing process of transmission lines.

Icing threatens the safe and stable operation of transmission lines. Accurate prediction of the icing process of conductor can help the work of anti-icing and disaster reduction of transmission lines. Generally, the icing of conductor is accompanied by the torsion process of conductor. Because of the interaction of conductor torsion and icing, there is a big difference of the icing shape and rate between different positions on a transmission line. In order to improve the accuracy of numerical calculation of conductor icing, a dynamic numerical calculation model of conductor icing torsion is established based on hydrodynamics and basic mechanics in this paper. Comprehensively, the model takes the effects of torsion angle and torsion icing shape on the icing process into consideration, including the effects on airflow filed and trajectories of water droplets in the air. Through the simulation, the change law of the torsion angle at different positions of the conductor, the influence characteristics of the conductor torsion on the icing process, and the differences of the icing torsion of conductor under different environmental parameters are analysed. The results show that, compared with the condition without torsion, the collision range of water droplets on the conductor is larger under the torsion condition, the average value of collision efficiency β1 is higher, and the icing rate is faster. The larger the wind velocity and the median volume diameter of water droplets in the air, the faster the conductor icing torsion development. [ABSTRACT FROM AUTHOR]