Dynamic ice accretion process and its effects on the aerodynamic drag characteristics of a power transmission cable model

An experimental study was conducted to examine the dynamic ice accretion process over the surface of a high-voltage power transmission cable model and characterize the effects of the ice accretion on the aerodynamic forces acting on the test model. The experimental study was carried out by leveraging the unique Icing Research Tunnel of Iowa State University (i.e., ISU-IRT) to generate typical wet glaze and dry rime icing conditions experienced by power transmission cables. A cylindrical power cable model, which has the same diameter as that of typical power transmission cables, was mounted in ISU-IRT for the ice accretion experiments. In addition to using a high-speed digital imaging system to record the dynamic ice accretion process, a novel digital image projection (DIP) based technique was utilized to quantify the 3D shapes of the ice structures accreted on the surface of the power cable model as a function of the ice accretion time. The time variations of the aerodynamic drag force acting on the test model during the dynamic ice accretion process were also measured quantitatively by using high-sensitive force/moment traducers mounted at two ends of the test model. The ice structures accreted over the surface of the power cable model were found to change significantly under different icing conditions (i.e., rime icing vs. glaze icing). The characteristics of the aerodynamic drag acting on the test model was found to vary significantly during the dynamic ice accretion process depending on what types of ice structures were accreted on the test model. The acquired snapshots of the ice accretion images and the measured 3D shapes of the accreted ice structures on the test model are correlated with the aerodynamic force measurement results to elucidate the underlying physics.