Numerical Modeling and Analysis of Lightning Strike Damage on Overhead Ground Wires

Evaluating thermal ablation damage is fundamental to understanding lightning-induced damage mechanisms in overhead ground wires, as it provides essential supporting data. This paper presents a numerical model that explicitly incorporates mass loss due to material vaporization at high temperatures to assess lightning-induced thermal ablation damage. Using this model, we analyze how mass loss affects thermal ablation damage evaluation and examine the contributions of Joule heating and lightning arc heat transfer under different lightning current components. Comparisons with published experimental data show that neglecting mass loss leads to significant deviations from model predictions. Under continuous current conditions, lightning arc heat transfer dominates thermal ablation. In contrast, under return stroke currents, the contribution of Joule heating increases significantly with current magnitude, reaching up to 25%. When the time step Δt is less than 60ms, the model output stabilizes, ensuring computational accuracy. Overall, this study offers essential theoretical guidance for accurately evaluating thermal ablation damage in overhead ground wires, laying a robust foundation for future studies of damage mechanisms under complex lightning conditions.