In this study. the authors developed a three-dimensional (3D) numerical model for the diffusion of positive corona charges based on a 2D model with a uniform grid to explore the characteristics of corona discharge at a building tip during a thunderstorm in the presence of wind. The variable-grid meshing method is used to solve the problems of implementing a large simulation domain for... https://seisukeknifes.shop/product-category/name-engraving-service/