Glaze icing process of moveable overhead conductor and its aerodynamic characteristics with numerical method

Abstract

There have been theoretical and experimental reports of glaze icing process which limited to fixed overhead power lines or cables, but very few are related to conductor motions, not to mention its effects on the conductor's aerodynamic characteristics. Thus, a preliminary study is conducted to demonstrate glaze icing process on a moveable overhead conductor and to discuss the effects of the conductor motions on water films, ice shapes and its corresponding aerodynamic characteristics. Based on lubrication theory, an analytical glaze accretion model on upwind side of the overhead conductor is established by considering water film thickness, ice thickness, conductor motions and joule heats. Wind pressures and frictions, and aerodynamic coefficients are computed with computational fluid dynamics(CFD) method. Comparison between the fixed conductors and the moveable conductors on water films and the ice shapes are carried out, and the effects of upper rivulets on aerodynamic vibrations of the iced conductors are discussed accordingly. The results shown that the conductor motion has obviously effect on the water films and upper rivulet positions, and further affected ice shapes. Moreover, in the glaze icing process, the conductor motion presented a kind of wind velocity and amplitude-restricted vibrations. It turns out proposed models can capture main features of glaze icing on the moveable overhead conductor and shed light on more actual glaze icing analysis.