Aerodynamic Flow Field and Mechanical Response of a Quad-Bundle Conductor–Stockbridge Damper System Under Sustained Wind Loading

Sustained winds can induce vibration and fretting wear at the hardware connections of quad-bundle conductors fitted with Stockbridge dampers. We developed a coupled dynamic model to characterize the unsteady flow field, aerodynamic loads, structural response, load transfer, and interface wear of this system. Numerical simulations resolved the instantaneous velocity and vorticity fields around the four sub-conductors and quantified their aerodynamic forces, displacements, accelerations, and dynamic tension. A local contact model combined with Archard’s law was then used to calculate interface forces, relative slip, and cumulative wear. Pronounced wake interference produced nonuniform aerodynamic loading among the sub-conductors. Sub-conductor C3 had the largest along-wind aerodynamic-force RMS (1.836 N), while the along-wind displacement RMS values of C1–C4 were 9.95, 6.63, 10.59, and 5.68 cm, respectively. Along-wind motion dominated vertical motion. The tension of C3 varied from 24.883 to 25.445 N over 2–12 s. Dampers D2 and D4 showed the largest displacement and acceleration responses. Cumulative slips at the damper clamp–conductor interface were 10.797, 15.013, 10.645, and 14.989 μm for D1–D4, respectively, and wear was concentrated at this interface. These results link wake interference to damper-interface loading and provide a basis for optimizing damper placement and assessing transmission-line reliability under sustained winds.