Numerical study of icing profiles and its effects on aerodynamic characteristics of stay cables

In cold and humid environments, ice accretion can significantly alter the aerodynamic characteristics of structures, leading to pronounced vibration problems in transmission lines, bridge cables, and wind turbine blades. Motivated by a field-observed cable vibration event, this study investigates the icing characteristics and aerodynamic performance of iced stay cables. Representative ice accretion profiles were first obtained through numerical simulations based on available meteorological conditions and icing parameters reported in previous studies. Wind tunnel experiments and numerical simulations were then combined to examine the aerodynamic characteristics, potential quasi-steady galloping susceptibility, and underlying mechanisms of three selected iced cable profiles. The results show that the simulated iced cable profiles reasonably capture the main geometric characteristics observed in the wind tunnel tests reported in the literature. In the numerical simulations, within the investigated diameter range of 0.20–0.225 m, cable diameter showed a limited influence on the ice accretion profile. Whereas LWC , wind speed, and temperature significantly affected the icing characteristics. Furthermore, increasing the LWC from 1 g/m³ to 1.5 g/m³ led to a transition in the iced cable profile from a crescent shape to a D -shape. Within the simulated wind speed range of 10–20 m/s, higher wind speeds increased the mass flux of impinging water droplets on the cable surface and enhanced overall surface heat exchange, thereby promoting ice accretion. The iced profiles formed at −1 °C and −3 °C exhibited potential quasi-steady galloping susceptibility. Specifically, negative galloping force coefficients (Cg < 0) were identified at attack angles of 22°–24° for the −1 °C profile and at −54° to −52° and 50° for the - 3 °C profile, whereas no negative Cg values were identified for the −5 °C profile. Moreover, further analysis of the flow field vorticity contours and surface pressure coefficients of the −1 °C profile at attack angles of 36° and 38° reveals that variations in the attack angle modify the flow separation behavior on the leeward side. The movement of the flow separation point is associated with a sharp drop in the lift coefficient of the cable cross-section, thereby providing a possible explanation for the potential quasi-steady galloping susceptibility.