Computational electromagnetics

About: Computational electromagnetics is a research topic. Over the lifetime, 6412 publications have been published within this topic receiving 113727 citations. The topic is also known as: Electromagnetic field analysis.

Computation of electromagnetic fields inside strongly inhomogeneous objects by the weak-conjugate-gradient fast-Fourier-transform method

Abstract: The computation of the electromagnetic field inside a strongly inhomogeneous dielectric object is formulated in terms of a domain-integral equation over the object. We discuss a weak form of the integral equation in which the spatial derivatives are integrated analytically. Doing so, we obtain an equation that is solved efficiently with the advantageous combination of a conjugate-gradient iterative method and a fast-Fourier-transform technique. Numerical computations are performed for a strongly inhomogeneous lossy sphere. For this case we compare the accuracy and the efficiency of the present method with the analytic solution based on the Mie series and the finite-difference time-domain approach. To show that the method is also capable of computing more-complex scattering problems, we assume the incident field to be generated by a (1/2)λ thin-wire dipole. In this case the absorbed power density is presented. All these test cases demonstrate that the weak form of the conjugate-gradient fast-Fourier-transform method can be considered as a comparatively simple and efficient tool for solving realistic electromagnetic wave-field problems.

Electromagnetic modeling of complex railgun geometries

Abstract: A model is developed to simulate the electro-magnetic behavior of arbitrarily shaped long parallel conductors in the high frequency limit. Specifically, the model solves the Laplace equation in a two-dimensional domain using discrete current sheets and a least square minimization solution technique. The model calculates the inductive current distribution on the surfaces of the conductors and the vector potential and B-fields in the space external to the conductors. This model (LAPLAC) is used to analyze a number of different conductor geometries typically found in railgun systems. A system of rails within a conducting coaxial cylinder is modeled and compared with a similar system without the conducting cylinder. A similar comparison is made between a simple rail system and one which contains an augumenting turn connected in series with the main rails. Performance of these configurations is compared based on the inductive and resistive characteristics associated with the high-frequency current distribution predicted by the LAPLAC model.

Topological Approach to Computational Electromagnetism

Abstract: Software systems designed to solve Maxwell's equations need abstractions that accurately explain what different kinds of electromagnetic problems really do have in common. Computational electromagnetics calls for higher level abstractions than what is typically needed in ordinary engineering problems. In this paper Maxwell's equations are described by exploiting basic concepts of set theory. Although our approach unavoidably increases the level of abstraction, it also simplifies the overall view making it easier to recognize a topological problem behind all boundary value problems modeling the electromagnetic phenomena. This enables us also to construct an algorithm which tackles the topological problem with basic tools of linear algebra.