A CFD modelling study of atmospheric particulate matter dry deposition on electrical insulators

Surface contamination of overhead power line insulators poses a significant risk to the reliability and operational continuity of electrical networks. This study develops and validates a three-dimensional Computational Fluid Dynamics (CFD) model to investigate dry aerosol deposition on a chain of U120B glass insulators, with a focus on the underlying aerodynamic mechanisms. The model employs an Eulerian-Lagrangian approach to resolve the coupled dynamics of turbulent airflow and particle transport, incorporating molecular and turbulent diffusion, inertial and gravitational effects, and a detailed representation of the insulator geometry. Validation against established experimental datasets confirms the model’s ability to accurately predict deposition velocities across a broad spectrum of particle sizes and flow regimes. Application of the framework reveals that local flow structures, such as recirculation zones, boundary layer separation, and adverse pressure gradients, influence the pollutants deposition spatial distribution, with different deposition velocities on the top and bottom surfaces of the insulators. The analysis demonstrates that wind speed and particle size critically influence deposition efficiency, with non-monotonic behaviours emerging under specific conditions. These findings provide a predictive, physics-based foundation for optimizing insulator design and maintenance strategies, supporting enhanced resilience of power systems to environmental contamination.