Study On FDTD Parallel Computing Method Of The Scattering Characteristic For The Hypersonic Vehicle

Finite-difference time-domain method as one of the most commonly used classical numerical simulation methods in computational electromagnetics has a lot of strong points such as wide application range and simple calculation.However,when studying the problem of electromagnetic scattering of hypersonic vehicle targets,the traditional serial FDTD method is faced with the disadvantages of long computation time and high memory requirements,which seriously hampers the research progress of simulation calculations for such problems.Nowadays,the serial FDTD method can not use the advantages of computer multi-core and multi-processor in the way of single-process running computing,At the same time,for the problem of electromagnetic scattering of complex electrically large objects,the memory size of conventional hardware devices is difficult to meet the calculation requirements.The paper takes advantage of the natural grid parallel iterative computation of the FDTD method and parallelizes the traditional FDTD method based on the Message Passing Interface Library(MPI),and the design ideas and framework of the parallel FDTD method are given.The implementation of MPI parallelization of FDTD algorithm is studied.The establishment of three-dimensional virtual topology structure,the communication process between processes,the division of computing area and so on are mainly discussed.The specific work of the paper is as follows:1.Based on the master-slave mode of MPI programming,using the Fortran programming language,parallel FDTD program development that can simulate the calculation of electromagnetic scattering in conventional media and non-magnetized plasma dispersion media was completed.Moreover,the radar cross section(RCS)of the conventional medium sphere and the plasma sphere was calculated and compared with the analytical results of the corresponding Mie theory,verifying the accuracy and stability of the parallel FDTD program.2.Based on the windows 7 system workstation equipment,the compile and run environment of MPICH2 software was set up,and parallel FDTD algorithm calculations were implemented on two high-memory,multi-core workstations.3.A parallel FDTD program was used to simulate the RCS of a typical hypersonic vehicle RAM-CII and the sheathed plasma sheath assembly target,and the electromagnetic scattering characteristics of the aircraft under different flight scenarios were analyzed,and the performance of the parallel program was compared.Under different parallel schemes with the same number of processes,the number of communication grids between the discovery processes has a greater impact on the computational time-consuming.Under the same number of processes,the preference for the parallel scheme with fewer communication grids can achieve the fastest calculation speed.4.Based on the high-performance cluster system,the parallel FDTD program is compiled,tested and calculated under the Linux system.Combining multiple nodes with multiple compute cores,the RCS of several typical aircraft targets are calculated in parallel,For different test environments with multi-node multi-core and single-node multi-core,the calculation performance of parallel FDTD programs was analyzed with specific examples.