Fully implicit double-time-step calculation method for time-varying electromagnetic field

Abstract

The invention provides a fully implicit double-time-step calculation method for a time-varying electromagnetic field, and the method comprises the steps of carrying out simulation modeling according to the physical background of an electromagnetic problem simulated by a target in combination with boundary condition information; encrypting quadrilateral or hexahedral structure grids of the numerical calculation area at wall surfaces and geometric singular positions, wherein the grids are gradually far away from scattering wall surfaces and are gradually sparse; outputting a grid data file and setting and outputting a boundary condition file; inputting target calculation electromagnetic parameters and numerical calculation control parameters; inputting grid data and a boundary condition information file, and initializing a calculation space electromagnetic field; and iteratively solving the time-varying electromagnetic field of the Maxwell equation set in an implicit double-time-step mode based on time iteration propulsion and space flux residual. A steady virtual time derivative item is introduced into a control equation, so that the physical time advance step length can be selected according to physical problems without being limited by stability, and the calculation performance is improved while high numerical precision is kept.

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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