Ion‐Flow Field Modelling of ± 1100 kV Transmission Lines Under Strong‐Wind Scenarios Using the Multiple Relaxation Time Lattice Boltzmann Method

ABSTRACT

To solve the ion‐flow field of ultrahigh‐voltage direct current (UHVDC) transmission lines under strong‐wind scenarios, the multiple relaxation time lattice Boltzmann method (MRT‐LBM) is adopted. Compared with previous ion‐flow studies predominantly based on the single relaxation time LBM, the MRT‐LBM framework provides improved numerical robustness under strong‐wind and strong‐electric‐field conditions. First, an MRT lattice Boltzmann equation is formulated to suppress oscillatory divergence commonly encountered in strong‐wind simulations. Then, a local mesh‐refinement strategy is implemented to efficiently address the multiscale characteristics of transmission line environments, and the model is validated against both analytical solutions and experimental measurements. Unlike most existing studies that focus on moderate wind conditions and simplified wind representations, this work applies the MRT‐LBM to simulate the ion‐flow field of a ± 1100 kV UHVDC transmission line under strong‐wind scenarios. Departing from conventional assumptions of spatially uniform crosswinds, both a power‐law wind profile and a turbulent wind field are employed to represent environmental winds, and the resulting numerical discrepancies are systematically investigated. Finally, variations in electric field intensity, ion‐current density and ground‐level unsafe regions under strong‐wind conditions are quantitatively analysed.