Experimental study on self-excited vibration of artificial imitation ice for real transmission lines

This paper proposes a selection method for artificial imitation ice. Using computational fluid dynamics simulations, the lift and drag coefficients of D-shaped, sector-shaped, and crescent-shaped iced conductor sections applicable to test lines were analyzed. The critical wind speed for galloping under these three icing cross sections was then calculated using the galloping critical wind speed formula. Full-scale truncated models with D-shaped, sector-shaped, and crescent-shaped artificial imitation ice cross sections were fabricated, and airflow excitation tests were conducted to induce galloping and record displacement responses. The most gallop-prone artificial imitation ice shape was determined, and the effects of surface roughness and weight on galloping behavior were further examined. The results show that under the same wind speed, the D-shaped ice exhibited the most pronounced galloping, with the largest amplitude and the earliest onset. Increasing the surface roughness of the artificial imitation ice reduced the maximum displacement of the D-shaped ice model and altered its divergent behavior, leading to a long-period “beating” pattern characterized by a continuous increase followed by a gradual decrease in amplitude. Increasing the weight of the artificial imitation ice did not significantly affect the maximum displacement during the initial growth phase but notably reduced the stabilized amplitude after galloping became steady. This study provides an effective test basis for analyzing the galloping mechanism of iced conductors and guiding anti-galloping design.