An updated equivalent oscillator model for VIV reproduction on transmission line conductors

Aeolian vibrations may occur on overhead transmission lines conductors when exposed to wind flows perpendicular to the span. If not adequately mitigated through suitable damping system, these vibrations can lead to fatigue failure of the conductors and associated fittings. The Energy Balance Principle (EBP) is commonly employed to predict the onset and behaviour of such vibrations. While EBP offers a simple and effective approach, its applicability becomes limited in certain scenarios, such as long-span crossings, where the assumption of spatially uniform wind turbulence is no longer valid. Purely mathematical models are often impractical due to their complexity and Computational Fluid Dynamic (CFD) models remain constrained by current computational capabilities. Consequently, semi-empirical models, such as equivalent oscillator, represent the best trade-off between accuracy and computational cost. These models can be used for a better understanding of field observations and for the design of effective damping systems. The oscillator linear and non-linear parameters, critical for accurately reproducing the Vortex-Induced Vibrations (VIV) phenomenon have been optimized using a Genetic Algorithm (GA) taking advantage of the experimental database collected in wind tunnel. A benchmark study, conducted using EBP software on a representative case, validated the model and facilitated the optimization of the number of oscillators required, thereby reducing computational costs. The model’s applicability has been further demonstrated through comparisons with field measurements and established reference models. With the prospective inclusion of turbulence effects in multimodal simulations, the tool is expected to support the optimization of damping systems even in complex scenarios, such as long-span crossings.