A Fully Implicit Dual-Time-step Calculation Method for Time-Varying Electromagnetic Field

Abstract

The present invention provides a fully implicit double-time-step calculation method for time-varying electromagnetic fields, which includes performing simulation modeling in combination with boundary condition information based on the physical background of the simulated electromagnetic problem of the target; quadrilateral or hexahedral grids in the numerical calculation area , it is encrypted at the wall and geometric singularity, and the grid gradually becomes sparser away from the scattering wall; output grid data files and set and output boundary condition files; input target calculation electromagnetic parameters, numerical calculation control parameters; input grid data and the boundary condition information file, initialize the calculation of the space electromagnetic field; iteratively solve the time-varying electromagnetic field of Maxwell's equations in an implicit dual time step method based on time iterative advance and space flux residual. By introducing a constant virtual time derivative term in the control equation, the physical time advancement step can be selected according to the physical problem without being restricted by stability, and the calculation performance can be improved while maintaining high numerical accuracy.

Description

technical field [0001] The invention relates to the technical field of time-domain numerical solution of electromagnetics, in particular to a fully implicit double-time-step calculation method that can improve the time-advancing efficiency of time-varying electromagnetic fields. Background technique [0002] For electromagnetic scattering of targets with complex shapes and electromagnetic interference in complex electromagnetic environments, time-domain methods can be used to simulate complex phenomena such as scattering, multiple scattering, hole penetration, cavity excitation, etc., and can accurately simulate time history more intuitively, unlike traditional high The frequency progressive method proposes a special treatment method for special components and special electromagnetic phenomena such as edge diffraction. [0003] The time-varying electromagnetic field in the time domain satisfies Maxwell's equations in the time domain. With the development of computer technolo...

AI Technical Summary

Problems solved by technology

However, the time-explicit method has one of the biggest flaws. Its time step is limited by stability, and the entire calculation space must adopt a uniform minimum global calculation step. The body-fitted dense mesh generated for simulating drastic changes in geometry (such as wing The geometric singularity of the front and rear edges brings about drastic changes in the electromagnetic field gradient, which requires careful simulation of dense grids and electromagnetic multi-scale problems), which will bring a small global time step, and large grid cells require more time steps in this The unit propagates the information, so that it takes a long time to calculate the stable time-varying electromagnetic field, especially when solving the time-domain problem of electromagnetic scattering of high-frequency and electrically large-scale targets, the small time step limited by the stability brings the time-domain electromagnetic field A significant increase in the amount of calculations consumes a large amount of computing resources

On the other hand, the implicit calculation method can relax the stability limit of the calculation step size, but it is accompanied by a decrease in time accuracy and encryption, which leads to an increase in the dimension of the coefficient matrix and increases the difficulty of matrix inversion operations.

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