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Two numerical methods for solving high frequency multiple scattering problems ; ; Geuzaine, Christophe Scientific conference (2011, October 04) Detailed reference viewed: 14 (1 ULg)A Frontal Delaunay Quad Mesh Generator Using the L ∞ Norm ; ; et al in Proceedings of the 20th International Meshing Roundtable (2011, October) Detailed reference viewed: 54 (11 ULg)Quality Surface Meshing Using Discrete Parametrizations ; ; Geuzaine, Christophe in Proceedings of the 20th International Meshing Roundtable (2011, October) Detailed reference viewed: 6 (0 ULg)A one Field Full Discontinuous Galerkin Method for Kirchhoff-Love Shells Applied to Fracture Mechanics Becker, Gauthier ; Geuzaine, Christophe ; Noels, Ludovic in Computer Methods in Applied Mechanics & Engineering (2011), 200(45-46), 3223-3241 In order to model fracture, the cohesive zone method can be coupled in a very efficient way with the Finite Element method. Nevertheless, there are some drawbacks with the classical insertion of cohesive ... [more ▼] In order to model fracture, the cohesive zone method can be coupled in a very efficient way with the Finite Element method. Nevertheless, there are some drawbacks with the classical insertion of cohesive elements. It is well known that, on one the hand, if these elements are present before fracture there is a modification of the structure stiffness, and that, on the other hand, their insertion during the simulation requires very complex implementation, especially with parallel codes. These drawbacks can be avoided by combining the cohesive method with the use of a discontinuous Galerkin formulation. In such a formulation, all the elements are discontinuous and the continuity is weakly ensured in a stable and consistent way by inserting extra terms on the boundary of elements. The recourse to interface elements allows to substitute them by cohesive elements at the onset of fracture. The purpose of this paper is to develop this formulation for Kirchhoff-Love plates and shells. It is achieved by the establishment of a full DG formulation of shell combined with a cohesive model, which is adapted to the special thickness discretization of shell formulation. In fact, this cohesive model is applied on resulting reduced stresses which are the basis of thin structures formulations. Finally, numerical examples demonstrate the efficiency of the method. [less ▲] Detailed reference viewed: 179 (66 ULg)Subproblem method with dual finite element formulations for accurate thin shell models Dang, Quoc Vuong ; Dular, Patrick ; V Sabariego, Ruth et al in Proceedings of the XV International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF2011) (2011, September) A subproblem method with dual finite element magnetostatic and magnetodynamic formulations is developed to correct the inaccuracies near edges and corners coming from thin shell models, that replace thin ... [more ▼] A subproblem method with dual finite element magnetostatic and magnetodynamic formulations is developed to correct the inaccuracies near edges and corners coming from thin shell models, that replace thin volume regions by surfaces. The surface-to-volume correction problem is defined as one of the multiple subproblems applied to a complete problem, considering successive additions of inductors and magnetic or conducting regions, some of these being thin regions. Each subproblem is independently solved on its own domain and mesh, which facilitates meshing and solving while controlling the importance and usefulness of each correction. Parameterized analyses of thin regions are efficiently performed. [less ▲] Detailed reference viewed: 136 (35 ULg)Subproblem finite element method for magnetic model refinements Dular, Patrick ; ; et al in Proceedings of the XV International Symposium on Electromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF2011) (2011, September) Model refinements of magnetic circuits are performed via a subproblem finite element method. A complete problem is split into subproblems with overlapping meshes, to allow a progression from source to ... [more ▼] Model refinements of magnetic circuits are performed via a subproblem finite element method. A complete problem is split into subproblems with overlapping meshes, to allow a progression from source to reaction fields, ideal to real flux tubes, 1-D to 2-D to 3-D models, perfect to real materials, with any coupling of these changes. Its solution is the sum of the subproblem solutions. The procedure simplifies both meshing and solving processes, and quantifies the gain given by each refinement on both local fields and global quantities. [less ▲] Detailed reference viewed: 53 (4 ULg)Impact of the mesh on the accuracy and efficiency of cardiovascular simulations ; Geuzaine, Christophe ; et al in Proceedings of the ECCOMAS Thematic International Conference on Simulation and Modeling of Biological Flows (SIMBIO 2011) (2011, September) Detailed reference viewed: 17 (0 ULg)On the Parameters of the Perfectly Matched Layer in Discrete Contexts Modave, Axel ; Delhez, Eric ; Geuzaine, Christophe in Proceedings of the 10th International Conference on Mathematical and Numerical Aspects of Waves (WAVES 2011) (2011, July 26) Perfectly Matched Layer (PML) techniques are widely used for dealing with unbounded problems. However their performance depends critically on both an absorption coefficient and the numerical method. The ... [more ▼] Perfectly Matched Layer (PML) techniques are widely used for dealing with unbounded problems. However their performance depends critically on both an absorption coefficient and the numerical method. The coefficient is generally tuned by using costly and case-dependent optimization procedures or set empirically. In this paper we present some efficient profiles of the coefficient that allow to avoid any tuning in discrete contexts. These profiles are compared by means of two benchmarks with different numerical methods. [less ▲] Detailed reference viewed: 105 (25 ULg)Optimization of the PML in the Discrete Context for Wave-Like Problems Modave, Axel ; Delhez, Eric ; Geuzaine, Christophe Conference (2011, July 18) The Perfectly Matched Layer (PML) is widely used for unbounded problems. However its performances depend critically on both an absorption coefficient and the numerical method. The coefficient is generally ... [more ▼] The Perfectly Matched Layer (PML) is widely used for unbounded problems. However its performances depend critically on both an absorption coefficient and the numerical method. The coefficient is generally tuned by using optimization procedures. In this talk we will present some efficient profiles of the coefficient that overcome every tuning in discrete contexts. These profiles and others will be compared by using benchmarks with different numerical methods. [less ▲] Detailed reference viewed: 99 (20 ULg)Stochastic Uncertainty Quantification of Eddy Currents in the Human Body by Polynomial Chaos Decomposition ; ; Vazquez Sabariego, Ruth et al Scientific conference (2011, July 07) Detailed reference viewed: 14 (4 ULg)Subproblem Approach for Thin Shell Dual Finite Element Formulations Dang, Quoc Vuong ; Dular, Patrick ; V Sabariego, Ruth et al in Proceedings of the 18th Conference on the Computation of Electromagnetic Fields (COMPUMAG2011) (2011, July) A subproblem technique is applied on dual formu- lations to the solution of thin shell finite element models. Both the magnetic vector potential and magnetic field formulations are considered. The ... [more ▼] A subproblem technique is applied on dual formu- lations to the solution of thin shell finite element models. Both the magnetic vector potential and magnetic field formulations are considered. The subproblem approach developed herein couples three problems: a simplified model with inductors alone, 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 is solved on its own independently defined geometry and finite element mesh. [less ▲] Detailed reference viewed: 93 (25 ULg)Electro-Mechano-Fluidic Modelling of Microsystems using Finite Elements ; ; et al in Proceedings of the 18th Conference on the Computation of Electromagnetic Fields (COMPUMAG 2011) (2011, July) Detailed reference viewed: 10 (0 ULg)Discontinuous Galerkin Method for Computing Induced Fields in Superconducting Materials" ; ; et al in Proceedings of the 18th Conference on the Computation of Electromagnetic Fields (COMPUMAG 2011) (2011, July) Detailed reference viewed: 8 (0 ULg)A Finite Element Subproblem Method for Position Change Conductor Systems Dular, Patrick ; ; V Sabariego, Ruth et al (2011, July) Analyses of magnetic circuits with position changes of both massive and stranded conductors are performed via a finite element subproblem method. A complete problem is split into subproblems associated ... [more ▼] Analyses of magnetic circuits with position changes of both massive and stranded conductors are performed via a finite element subproblem 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 benefit from the developed approach. [less ▲] Detailed reference viewed: 24 (4 ULg)Quality meshing algorithms for accurate and efficient cardiovascular simulations ; ; et al in Nithiarasu, P.; Lohner, R. (Eds.) Procedings of the 2nd International Conference on Mathematical and Computational Biomedical Engineering (CMBE2011) (2011, April) Detailed reference viewed: 12 (0 ULg)Quality surface meshing using discrete parametrizations ; ; et al in Proceedings of the 16th International Conference on Finite Elements in Flow Problems (FEF 2011) (2011, March) Detailed reference viewed: 10 (0 ULg)Blossom-Quad: a non-uniform quadrilateral mesh generator using a minimum cost perfect macthing algorithm ; Geuzaine, Christophe ; in Wall, W. A.; Gravemeier, V. (Eds.) Proceedings of the 16th International Conference on Finite Elements in Flow Problems (FEF 2011) (2011, March) Detailed reference viewed: 30 (0 ULg)New Non-Overlapping Domain Decomposition Algorithm for the Helmholtz Equation ; ; Geuzaine, Christophe in Proceedings of the 20th International Conference on Domain Decomposition Methods (DD20) (2011, February) Detailed reference viewed: 14 (0 ULg)Correction of Thin Shell Finite Element Magnetic Models via a Subproblem Method Dular, Patrick ; Dang, Quoc Vuong ; Vazquez Sabariego, Ruth et al in IEEE Transactions on Magnetics (2011), 47(5), 1158-1161 A subproblem finite-element method is developed for correcting the inaccuracies near edges and corners inherent to thin shell models, for both magnetostatic and magnetodynamic problems. A thin shell ... [more ▼] A subproblem finite-element method is developed for correcting the inaccuracies near edges and corners inherent to thin shell models, for both magnetostatic and magnetodynamic problems. A thin shell solution, supported by a simplified mesh near the thin structures, serves as a source of a correction problem with the actual volumic thin regions alone in a homogeneous medium, concentrating the meshing effort on the thin regions only. Improvements of local fields are efficiently achieved and allow accurate force and loss calculations. [less ▲] Detailed reference viewed: 29 (11 ULg)Finite Element Computational Homogenization of Nonlinear Multiscale Materials in Magnetostatics Niyonzima, Innocent ; V Sabariego, Ruth ; Dular, Patrick et al in 18th Conference on the Computation of Electromagnetic Fields (COMPUMAG2011) (2011) This paper deals with the modelling of nonlinear multiscale materials in magnetostatics by means of a finite element computational homogenization method. The method couples a macroscale problem with many ... [more ▼] This paper deals with the modelling of nonlinear multiscale materials in magnetostatics by means of a finite element computational homogenization method. The method couples a macroscale problem with many microscale problems. During the upscaling step, the homogenized magnetic permeability and its derivative with respect to the magnetic field are calculated from the microscale solution and transferred to the macroscale. The downscaling step consists in imposing proper boundary conditions for the microscale problems from the macroscale solution. Results are validated by comparison with those obtained with classical finite element brute force approach. [less ▲] Detailed reference viewed: 90 (18 ULg) |
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