A Meshless Method for Trajectory Simulation of Charged Particles in Static Axisymmetric Electric and Magnetic Fields

The meshless method has strong abilities for conformal modeling and multiphysics coupling. This study pioneers the application of the meshless local Petrov-Galerkin (MLPG) method in the trajectory simulation of charged particles in static axisymmetric electric and magnetic fields, enhancing simulation accuracy and simplifying the treatment of multiphysics coupling issues. The MLPG method is introduced to solve the electric field. Then the field mapping between the electric field and electron trajectories can be easily realized by combining the node sets, which are used to discretize the problem domain and the electron trajectories. In the mapping process, a simple interface processing technique is also proposed. The numerical experiments indicate that the MLPG method has a higher accuracy than the traditional finite difference method (FDM) and finite element method (FEM) under the same element size. The proposed meshless-based method is also verified by analyzing the magnetron injection gun (MIG) of an 800 GHz gyrotron and comparing the results with the particle-in-cell (PIC) simulation.