Three-Dimensional Parallel Electromagnetic Particle-in-Cell Simulation Algorithms And Its Applications

As the rapid development of computer technology, electromagnetic particle-in-cell (PIC) simulation method has played a more and more important role in the research of issues related to electromagnetic radiation and self-consistant field since 1950s. However, electromagnetic PIC simulation is very time-consuming, parallel computing is regarded as the best method to overcome this disadvantage. In this paper, the three-dimensional (3-D) parallel electromagnetic PIC simulation algorithms have been investigated completely and deeply.The main research is as follows:1. Study of the 3-D parallel electromagnetic PIC simulation algorithms based on the message passing model. The advance of PIC simulation in one time step is divided into two computational procedures, which are procedure of updating electromagnetic fields and procedure of particle push. Based on partitioning the simulation space along one direction, the parallel alogirthms of the two procedures are designed separately in both Cartesian coordinate system and cylindrical coordinate system. The parallel alogirthms of the two procedures are integrated and optimized. The cause of the simulation space can't be partitioned along the angular direction in cylindrical coordinate system is analysed. The parallel algorithms based on partitioning the simulation space along one direction are extended to the cases of partitioning the simulation space along two directions or three directions.2. More study of the 3-D parallel electromagnetic PIC simulation algorithms based on the message passing model. The improved 3-D parallel electromagnetic PIC simulation algorithms are designed, which can reduce once of process synchronization in one time step. A kind of dynamic load balancing algorithm of 3-D parallel electromagnetic PIC simulation is researched, which promotes parallel speedup by repartitioning the simulation space according to the load difference between processes. A kind of gradient non-uniform gird generation algorithm is designed, based on the algorithm, the 3-D parallel PCl code LIAPIC is developed, which is specifically used for simulating the beam transport system of LIA concurrently. 3. Study of the 3-D parallel electromagnetic PIC simulation algorithms based on the shared storage model. The electromagnetic PIC simulation contains three key computational procedures: solving Maxwell's equations, solving Lorentz equation and particle motion equation, updating charge density and current density. Based on OpenMP, the parallel algorithms of all procedures are designed separately, the performance of which is tested and analyzed. The 3-D parallel electromagnetic PIC simulation algorithms based on the OpenMP/MPI hybrid model are also researched.4. Applications of 3-D parallel electromagnetic PIC simulation. The parallel computing capability of CHIPIC-3D is implemented, which is used for simulating many kinds of high power microwave sources, extended interaction oscillator (EIO), gyrotron and magnetically insulated transmission line (MITL). The beam transport process of a kind of linear induction accelerator (LIA) is simulated by LIAPIC, the beam transport system is almost 50 meters, which consists of 18 accelerating parts.