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arXiv · 2307.00278

A space-time finite element method for the eddy current approximation of rotating electric machines

Peter Gangl·Mario Gobrial·Olaf Steinbach
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Abstract

In this paper we formulate and analyze a space-time finite element method for the numerical simulation of rotating electric machines where the finite element mesh is fixed in space-time domain. Based on the Babuška--Nečas theory we prove unique solvability both for the continuous variational formulation and for a standard Galerkin finite element discretization in the space-time domain. This approach allows for an adaptive resolution of the solution both in space and time, but it requires the solution of the overall system of algebraic equations. While the use of parallel solution algorithms seems to be mandatory, this also allows for a parallelization simultaneously in space and time. This approach is used for the eddy current approximation of the Maxwell equations which results in an elliptic-parabolic interface problem. Numerical results for linear and nonlinear constitutive material relations confirm the applicability, efficiency and accuracy of the proposed approach.

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Peter Gangl, Mario Gobrial, Olaf Steinbach. 2023-07-01. A space-time finite element method for the eddy current approximation of rotating electric machines. https://doi.org/10.1515/cmam-2024-0033

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