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Time-domain finite-element modelling of laminated iron cores – Large skin effect homogenization considering the Jiles-Atherton hysteresis model Vazquez Sabariego, Ruth ; Niyonzima, Innocent ; Geuzaine, Christophe et al in Proceedings of the 15th Biennial IEEE Conference on Electromagnetic Field Computation (CEFC2012) (2012, November) This paper deals with the incorporation of the Jiles- Atherton (J-A) hysteresis model in a time-domain finite-element homogenization technique for laminated iron cores. The separate discretization of each ... [more ▼] This paper deals with the incorporation of the Jiles- Atherton (J-A) hysteresis model in a time-domain finite-element homogenization technique for laminated iron cores. The separate discretization of each lamination is avoided by using dedicated skin-effect basis functions, which also serve to interpolate the J- A hysteretic material law. As validation test case, a stacked ring core surrounded by a toroidal coil is considered. [less ▲] Detailed reference viewed: 97 (11 ULg)An optimum PML for scattering problems in the time domain Modave, Axel ; Delhez, Eric ; et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC 2012) (2012, July 05) The Perfectly Matched Layer (PML) is widely used for unbounded problems. However its performances depend critically on an absorption coefficient. This coefficient is generally tuned by using case ... [more ▼] The Perfectly Matched Layer (PML) is widely used for unbounded problems. However its performances depend critically on an absorption coefficient. This coefficient is generally tuned by using case-dependent optimization procedures. In this paper we will present some efficient profiles of the coefficient that overcome every tuning. These profiles and others will be compared by using a scattering benchmark solved with the Discontinuous Galerkin method. [less ▲] Detailed reference viewed: 95 (16 ULg)Subproblem h-Conform Magnetodynamic Finite Element Formulation for Accurate Model of Multiply Connected Thin Regions Dang, Quoc Vuong ; Dular, Patrick ; Vazquez Sabariego, Ruth et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC 2012) (2012, July 03) A subproblem $\vh$-conform eddy current finite element method is proposed for correcting the inaccuracies inherent to thin shell models. Such models replace volume thin regions by surfaces but neglect ... [more ▼] A subproblem $\vh$-conform eddy current finite element method is proposed for correcting the inaccuracies inherent to thin shell models. Such models replace volume thin regions by surfaces but neglect border effects in the vicinity of their edges and corners. The developed surface-to-volume correction problem is defined as a step of the multiple subproblems applied to a complete problem, consisting of inductors and magnetic or conducting regions, some of these being thin regions. The general case of multiply connected thin regions is considered. [less ▲] Detailed reference viewed: 70 (20 ULg)Evaluation de l'efficacité de blindage de parois hétérogènes par une méthode de Galerkin discontinue en domaine temporel ; Modave, Axel ; et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC 2012) (2012, July 03) Detailed reference viewed: 52 (10 ULg)Multiscale Quasistatic Homogenization for Laminated Ferromagnetic Cores Niyonzima, Innocent ; Vazquez Sabariego, Ruth ; Dular, Patrick et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC 2012) (2012, July 03) In this paper, we investigate the modeling of ferromagnetic multiscale materials. We propose a computational homogenization method based on the heterogeneous multiscale method (HMM) with inclusion of a ... [more ▼] In this paper, we investigate the modeling of ferromagnetic multiscale materials. We propose a computational homogenization method based on the heterogeneous multiscale method (HMM) with inclusion of a hysteresis model. The HMM involves: 1) a macroscale problem that captures the slow variations of the overall solution; 2) many microscale problems that allow to determine the constitutive law at the macroscale. At the microscale, a novel energy consistent hystere- sis model is incorporated. As application example, a laminated iron core is considered. [less ▲] Detailed reference viewed: 112 (25 ULg)ONELAB: Open Numerical Engineering LABoratory Geuzaine, Christophe ; ; et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC2012) (2012, July) Detailed reference viewed: 134 (14 ULg)A dynamical model with hysteresis for the homogenization of ferromagnetic laminated cores ; Niyonzima, Innocent ; et al in Proceedings of the 7th European Conference on Numerical Methods in Electromagnetism (NUMELEC2012) (2012, July) Detailed reference viewed: 69 (17 ULg)Le monde à l'envers : résoudre des EDPs pour construire des maillages Geuzaine, Christophe Scientific conference (2012, June 05) Detailed reference viewed: 52 (6 ULg)Improved Domain Decomposition Method for the Helmholtz Equation Thierry, Bertrand ; ; et al in Proceedings of the 21th International Conference on Domain Decomposition Methods (DD21) (2012, June) Detailed reference viewed: 48 (4 ULg)Combining Full Transients and Phasor Approximation Models in Power System Time Simulation Plumier, Frédéric ; Fabozzi, Davide ; Geuzaine, Christophe et al in Proceedings of the 21th International Conference on Domain Decomposition Methods (DD21) (2012, June) Detailed reference viewed: 164 (33 ULg)Optimisation des PML dans des contextes discrets Modave, Axel ; Delhez, Eric ; Geuzaine, Christophe Conference (2012, May 21) Detailed reference viewed: 59 (8 ULg)Imposing periodic boundary condition on arbitrary meshes by polynomial interpolation Nguyen, Van Dung ; Béchet, Eric ; Geuzaine, Christophe et al in Computational Materials Science (2012), 55 In order to predict the effective properties of heterogeneous materials using the finite element approach, a boundary value problem (BVP) may be defined on a representative volume element (RVE) with ... [more ▼] In order to predict the effective properties of heterogeneous materials using the finite element approach, a boundary value problem (BVP) may be defined on a representative volume element (RVE) with appropriate boundary conditions, among which periodic boundary condition is the most efficient in terms of convergence rate. The classical method to impose the periodic boundary condition requires the identical meshes on opposite RVE boundaries. This condition is not always easy to satisfy for arbitrary meshes. This work develops a new method based on polynomial interpolation that avoids the need of matching mesh condition on opposite RVE boundaries. [less ▲] Detailed reference viewed: 658 (315 ULg)Improved Finite Element Solvers for the Helmholtz Equation at High Frequencies Geuzaine, Christophe Scientific conference (2012, March 29) Detailed reference viewed: 32 (2 ULg)Improved Domain Decomposition Method for the Wave Equation in Harmonic Regime Geuzaine, Christophe ; ; et al in Proceedings of the 6th Advanced Computational Electromagnetics workshop (ACE 2012) (2012, March) Detailed reference viewed: 31 (2 ULg)Deux méthodes numériques pour la résolution de problèmes de diffraction multiple à haute fréquence ; ; Geuzaine, Christophe Scientific conference (2012, February 10) Detailed reference viewed: 16 (1 ULg)Blossom-Quad: a non-uniform quadrilateral mesh generator using a minimum cost perfect matching algorithm ; ; et al in International Journal for Numerical Methods in Engineering (2012), 89(9), 1102-1119 A new indirect way of producing all-quad meshes is presented. The method takes advantage of a well-known algorithm of the graph theory, namely the Blossom algorithm, that computes the minimum-cost perfect ... [more ▼] A new indirect way of producing all-quad meshes is presented. The method takes advantage of a well-known algorithm of the graph theory, namely the Blossom algorithm, that computes the minimum-cost perfect matching in a graph in polynomial time. The new Blossom-Quad algorithm is compared with standard indirect procedures. Meshes produced by the new approach are better both in terms of element shape and in terms of size field efficiency. [less ▲] Detailed reference viewed: 136 (14 ULg)Subproblem Approach for Thin Shell Dual Finite Element Formulations Dang, Quoc Vuong ; Dular, Patrick ; Vazquez Sabariego, Ruth et al in IEEE Transactions on Magnetics (2012), 48(2), 407-410 A subproblem technique is applied to dual thin shell finite element formulations. Both the magnetic vector potential and magnetic field formulations are considered. The subproblem approach developed ... [more ▼] A subproblem technique is applied to dual thin shell finite element formulations. Both the magnetic vector potential and magnetic field formulations are considered. The subproblem approach developed herein couples three problems: a simplified model with only inductors, a thin region problem using approximate interface conditions and a correction problem to improve the accuracy of the thin shell approximation, in particular near their edges and corners. Each problem has its own geometry and is solved on its associated finite element mesh. [less ▲] Detailed reference viewed: 78 (25 ULg)A Finite Element Subproblem Method for Position Change Conductor Systems Dular, Patrick ; ; Vazquez Sabariego, Ruth et al in IEEE Transactions on Magnetics (2012), 48(2), 403-406 Analyses of magnetic systems with position changes of both massive and stranded conductors are performed via a finite element sub- problem method. A complete problem is split into subproblems associated ... [more ▼] Analyses of magnetic systems with position changes of both massive and stranded conductors are performed via a finite element sub- problem method. A complete problem is split into subproblems associated with each conductor and the magnetic regions. Each complete solution is then expressed as the sum of subproblem solutions supported by different meshes. The subproblem procedure simplifies both meshing and solving processes, with no need of remeshing, and accurately quantifies the effect of the position changes of conductors on both local fields, e.g., skin and proximity effects, and global quantities, e.g., inductances and forces. Applications covering parameterized analyses on conductor positions to moving conductor systems can benefit from the developed approach. [less ▲] Detailed reference viewed: 42 (10 ULg)Time-domain surface impedance boundary conditions enhanced by coarse volume finite-element discretisation Vazquez Sabariego, Ruth ; Geuzaine, Christophe ; Dular, Patrick et al in IEEE Transactions on Magnetics (2012), 48(2), 631-634 In computational magnetodynamics, surface impedance boundary conditions allow to accurately account for high-frequency flux components while removing the massive conducting regions from the computation ... [more ▼] In computational magnetodynamics, surface impedance boundary conditions allow to accurately account for high-frequency flux components while removing the massive conducting regions from the computation domain. The time-domain approach previously proposed by the authors relies on the spatial discretisation of a 1-D eddy-current problem by means of dedicated basis functions derived from the analytical frequency-domain solution. In this paper, these time-domain impedance conditions are combined with a coarse volume finite-element discretisation of the massive conductors to capture slowly varying flux components. The accuracy of the hybrid approach can further be improved by introducing a fictitious frequency-dependent conductivity. The method is illustrated and validated by means of 1-D and 2-D test cases in the frequency and time domain. [less ▲] Detailed reference viewed: 47 (8 ULg)Improved Domain Decomposition Method for the Helmholtz Equation" Geuzaine, Christophe ; ; et al Scientific conference (2012, January 23) Detailed reference viewed: 42 (2 ULg) |
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