GPU-PIC Simulation Study Of New Electric Vacuum Devices

The increasing demand for high-performance electric vacuum devices promotes the rapid development of various new types of electric vacuum devices.However,most of these devices adopt high-frequency structures,which limits the traditional large-signal program,or even makes it no longer applicable.Moreover,three-dimensional electromagnetic particle-in-cell(PIC)simulation has become the main simulation way,but its efficiency is extremely low.In this case,the combination of PIC method and GPU parallel technology is expected to become a feasible and efficient simulation method.The PIC method directly solves the active Maxwell equations and the relativistic Lorentz equation of motion according to the boundary conditions and initial conditions of the newly designed vacuum device,while analyzing the real state of the evolution of the physical process accurately;GPU parallel technology utilizes the large-scale parallel processor core of GPU chip,which can highly parallelize computationally intensive tasks,greatly improving the computational efficiency of the program and the engineering application value of the PIC method.According to the above research background and research needs,this paper carries out an in-depth research on the utilization of PIC method and GPU technology based on a new electric vacuum device from following aspects:This paper describes the important role of vacuum electronic devices in the social development process.Through extensive research of electromagnetic particle simulation software at home and abroad,people have found out the advantages and significance of the use of PIC method and GPU technology in the development of new electric vacuum devices.This has laid foundation for the research work of this paper.Based on the serial code of the cold cavity field developed by the author's team,according to the actual design requirements of the PIC serial programs and the PIC parallel programs,this paper selects the appropriate particle push algorithm and current source allocation algorithm,and presents the algorithmic derivation of the core steps in the 3D electromagnetic PIC simulation process.The simulation process of the PIC method electromagnetic model is deeply analyzed.It gives the subtle processing of the particle motion module and the current source distribution module.The overall implementation scheme of the PIC serial program is established,and then the development is further developed based on the cold cavity field program.The particle motion module and the current source density distribution module program implement a PIC serial program based on a novel electric vacuum device.The folding waveguide interaction model is established.At the same time,the commercial software CST is used as the reference for simulation verification.The comparison verification results and error analysis are given to ensure the accuracy of the serial PIC program.This paper deeply analyzes the computationally intensive modules in the PIC method and formulates a reasonable paralleled scheme for each module's specific situation.The parallel PIC program development is implemented on the GPU,and then simulates the folded waveguide interaction structure by the serial program and the parallel program.Through the verification results and error analysis,the correctness of the parallel program can be guaranteed.Finally,this paper tests and analyses the parallel program's speed-up ratio.