An experimental study of dynamic icing process on an Aluminum-Conductor-Steel-Reinforced power cable with twisted outer strands

Abstract

An experimental campaign was conducted to investigate the dynamic icing process on an Aluminum-Conductor-Steel-Reinforced (ACSR) power cable with twisted outer strands and characterize the resultant wind loads experienced by the power cable under both dry rime and wet glaze icing conditions. In addition to recording the dynamic icing process over the cable surface with a high-resolution imaging system, the three-dimensional (3D) shapes of the ice layers accreted on the cable model were also quantified by using a novel 3D profile scanning system. While the evolution of the wake flow behind the iced ACSR cable was quantified with a Particle Image Velocimetry (PIV) system, the variation of the wind loads experienced by the cable model was also examined based on the measurements of force/moment transducers. Under the dry rime icing condition, opaque, grainy ice was found to accrete only within the impinging zone of airborne water droplets over the cable frontal surface without any noticeable water runback flow over the cable surface. In comparison, substantial unfrozen water was observed to run back over the cable surface under the wet glaze icing condition, causing the formation of transparent, glazy ice layer over a much wider area over the cable surface. Correlating with the formation of more complicated glazy ice humps/horns over the ACSR cable surface, the accumulated ice mass was found to grow much faster during glaze icing process, in comparison to that of rime icing case. While the resultant wind loads acting on the iced ACSR cable was found to decrease gradually with the increasing icing time under the rime icing condition, the corresponding values were found to increase continuously under the glaze icing condition.