Combining Full Transients and Phasor Approximation Models in Power System Time Simulation

in Proceedings of the 21th International Conference on Domain Decomposition Methods (DD21) (2012, June)

Imposing periodic boundary condition on arbitrary meshes by polynomial interpolation

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 ▲]

Improved Domain Decomposition Method for the Wave Equation in Harmonic Regime

in Proceedings of the 6th Advanced Computational Electromagnetics workshop (ACE 2012) (2012, March)

A Finite Element Subproblem Method for Position Change Conductor Systems

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 ▲]

Subproblem Approach for Thin Shell Dual Finite Element Formulations

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 ▲]

Computation of induced fields into the human body by dual Finite Element formulations

in IEEE Transactions on Magnetics (2012), 48(2), 783-786

Discontinuous Galerkin Method for Computing Induced Fields in Superconducting Materials

in IEEE Transactions on Magnetics (2012), 48(2), 591-594

Finite Element Computational Homogenization of Nonlinear Multiscale Materials in Magnetostatics

in IEEE Transactions on Magnetics (2012), 48(2), 587-590

The increasing use of composite materials in the technological industry (automotive, aerospace, ...) requires the development of effective models that account for the complexity of the microstructure of ... [more ▼]

The increasing use of composite materials in the technological industry (automotive, aerospace, ...) requires the development of effective models that account for the complexity of the microstructure of these materials and the nonlinear behaviour they can exhibit. In this paper we develop a multiscale computational homogenization method for modelling nonlinear multiscale materials in magnetostatics based on the finite element method. The method solves the macroscale problem by getting data from certain microscale problems around some points of interest. The missing nonlinear constitutive law at the macroscale level is derived through an upscaling from the microscale solutions. The downscaling step consists in imposing a source term and determining proper boundary conditions for microscale problems from the macroscale solution. For a two-dimensional geometry, results are validated by comparison with those obtained with a classical brute force finite element approach and a classical homogenization technique. The method provides a good overall macroscale response and more accurate local data around points of interest. [less ▲]

A Primal/Dual Approach for the Accurate Evaluation of the Electromechanical Coupling in MEMS

in Finite Elements in Analysis & Design (2012), 49(1), 19-27

Efficient Evaluation of the Geometrical Validity of Curvilinear Finite Elements

in Proceedings of the 5th international conference on Advanced COmputational Methods in ENgineering (ACOMEN 2011) (2011, November 14)