Study And Application Of Electromagnetic Particle-in-cell Several Key Technologies For Large-Scale High Power Microwave Device

Since the1950s, the method of calculation has played a key role in comprehendingand developing the vacuum electron devices, as well as in the application of the HighPower Microwave (HPM) device. The PIC method is always called the first-principlemethod in caculating the HPM sources. At present, it’s one of the most widely used andcredible methods in vacuum electronics. With the development for decades, this methodhas been matured gradually. However, there are still many aspects needed to beinnovated and improved.First, along with the development of research, a large number of new boundaryconditions have been proposed and many old boundary conditions are also need to beimproved constantly for the more accurate study. Therefore, the study of the boundaryconditions is a long process with continuous improvement and development.Secondly, by the mode、spectrum and accuracy requirements of the designeddevice is increasing, more and more devices which have large scales or fine grid cannotparse and calculate because of the limitation of the computer memory.Besides, in thefield of HPM source, generally the actual microwave tubes always have mode converteror antenna, etc. Because of some factors, such as load mismatching or mode cutoff, theexperimental results often do not equate with the numerical simulation results. At thistime, the semi-empirical and semi-theoretical conjecture instead of theoretical analysisis used, which consume a large number of manpower, material resource and money.Simulation for the whole device system is difficult to achieve because of the memorylimit.Finally, for the large-scale、high-precision device or device system, even itssimulation can be implemented, the calculation amount will be very huge. Therefore,efficient for hundreds of cores to calculate at the high-performance cluster, even asupercomputer can shorten the calculation time over tens or even hundreds times. In thisway, the parameter test and experimental comparison function can be implemented.Based on these situations, in this paper, the simulation algorithm of large-scaledevices is studied based on the electromagnetic PIC theory and algorithm, and large-scale devices are simulated with the implementation and improvement of a fewcommon boundary conditions. Finally, the applications are studied in detail on the basisof multicore and high efficient parallel computation at the high performance cluster. Themain topics in this thesis are as follows:1. Boundary conditions of electromagnetic PIC method are discussed detailedly.The boundary conditions are divided into field and particle boundary condition andparticle emission boundary condition which are detailed studied in this paper.2. The three-dimensional electromagnetic PIC algorithm based on segmentedanalysis has been realized,and improved after some confirmatory simulation. Based onelectromagnetic PIC method and the normal parallel algorithm, The three-dimensionalelectromagnetic PIC algorithm based on segmented analysis has been proposed andrealized. Then the improved large-scales device simulation parallel algorithm isintroduced and achieved. The algorithm based on divisional modeling and subsectionanalysis has been improved in three aspects. According to modeling and conectorgriding algorithm,the overall modeling、section analysis method has been put forward;In terms of particle calculate and information exchange algorithm also haveimproved;And in the parallel timing,computing efficiency increases by reducing aprocess synchronization at each time step.3. The high-performance calculation study of three-dimensional full-electromagnetic system simulation parallel software is introduced. The CHIPIC3D isworked at the HPC of Windows system and Linux system. The object oriented userinterface is developed by using NCARG image library and NCL language on Linuxsystem, and data diagnosis system based on the JADLib library and Javis software isrealized.4. The application of three-dimensional full-electromagnetic simulation parallelalgorithm based on segmented analysis is researched on CHIPIC3D platform. It’s usedto simulate several electrically large-scale devices. The simulated results verify thecorrectness of the algorithmic and the design or debugging role for experiment.