Modeling of the effect of a thermoelectric magnetic force onto conducting particles immersed in the liquid metal

International audienceSimulation of a thermo-electromagnetic force which acts on a conducting particle immersed into liquid metal is performed using multi-gird multi-physics software AEQUATIO. To verify numerical solutions a model thermoelectric problem is solved using two methods. In the first one a phase function is used to indicate the phase transition whereas in the second the solid particle is described with a real frontier of a simplified shape. Numerical and analytical solutions for a model problem qualitatively agree but strong oscillations are observed in a numerical solution with a phase function. Further AEQUQTIO is applied for calculation of the velocity of a dendrite fragment observed in-situ in experiment of solidification of AlCu alloy. Numerical solution gives a good agreement with the experimental observation

3-D Multistrands Inductor Modeling: Influence of Complex Geometrical Arrangements

International audienceWe study multistrands inductors in the context of high-frequency induction processes. They present the advantage of reducing Joule losses compared with solid inductors. We remind why that type of cable seems to be promising and what electromagnetic effects are already identified. We have to understand precisely what happens inside the inductor. Numerical simulation of the electromagnetic behavior of these objects is complicated due to the complexity of their 3-D geometry and to the size of the generated numerical system. We have developed a 3-D electromagnetic software based on an integral methods using classical Biot and Savart law. We applied this model for the simulation of multistrands cables with helical arrangement of strands. Execution time is reduced by the parallelization of the system building and the solver. We present some results obtained with 3-D simulations using integral methods for different configurations

3D Numerical modelling of multistrands inductors

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Toward the numerical simulation of grain structure in photovoltaic silicon ingots.

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AEQUATIO : un solveur EF multi-équations, multi-maillages

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Electromagnetic modeling with 3D integral method

International audienceThe present work focus on numerical modeling of electromagnetic phenomenon in the inductive processes. Our objective is to be able to model 3D configurations, taking into account high number of objects, small space between active elements of the installation and multi-scale. To achieve this goal we develop an integral method with parallel computing. The obtained results show the efficiency of this approach

Numerical modelling of electromagnetically-driven turbulent flows using LES methods

We deal with the prediction of electromagnetically-driven turbulent flows by means of a large-eddy-simulation method (LES). The model is applied in the case of a liquid metal pool submitted to a polyphase linear electromagnetic stirrer. We investigate two cases: (i) the effects of the pulsating part of the Lorentz forces are neglected, the frequency of the applied magnetic field being high enough; (ii) the oscillating part of the electromagnetic forces is taken into account, the frequency of the magnetic field being sufficiently low. The LES predictions agree well with the mean velocity measurements, as does the standard k–ε model. However, as for the turbulent kinetic energy predictions, there is a large discrepancy between the two models. When the oscillating part of the Lorentz forces is taken into account, the computations show that the fluid flow is sensitive to the unsteady part of the forces provided the frequency of the magnetic field is sufficiently low. The mean velocity is not affected by the fluctuating component of the force. As for the turbulence parameters, the presence of the pulsating part leads to a significant reduction of the turbulent kinetic energy, whilst the turbulence length scale decreases. The effect of the oscillating part of the Lorentz forces becomes negligible when the magnetic field frequency exceeds approximately 5 Hz

Résolution des équations thermo-électriques 3D couplées par la méthode des éléments finis. Application à un four polyphasé

The numerical simulation of industrial devices where heat transfer is obtained by electrical conduction, generally leads to the simultaneous resolution of electrical and thermal equations coupled by electrical properties often strongly linked with temperature. After describing physical phenomena equations, a finite element discretization of partial derivative equations is presented. Fifteen different formulations have been generated with the FLUX-EXPERT package allowing the modelization of many industrial systems in 2D, axisymetric or 3D geometries with or without equations coupling. Modelized problems are generally non linear and complicated. Matrices systems are dissymetric and ill-condionned. In order to optimize the resolution a Newton Raphson algorithm is used. Two applications are treated : i) a glass furnace with balanced and unbalanced AC supply ; ii) a traveling fluid heated by electrical conduction with DC supply.La simulation numérique de dispositifs industriels de chauffage par conduction électrique conduit à la résolution simultanée des équations électrique et thermique couplées par les propriétés électriques souvent fortement dépendantes de la température. Après une mise en équation des phénomènes physiques, la discrétisation en éléments finis des équations aux dérivées partielles est présentée. Quinze formulations différentes ont été générées à l'aide du logiciel FLUX-EXPERT, permettant ainsi de modéliser de nombreuse configurations industrielles (2D, axisymétriques et 3D) avec ou sans couplage fort entre les équations. Les problèmes modélisés sont généralement non linéaires et complexes. Ils conduisent à des systèmes mal conditionnés dissymétriques. Afin d'en optimiser la résolution un algorithme de Newton Raphson est utilisé. Deux installations industrielles ont été étudiées : i) un four à verre alimenté en tension polyphasée équilibrée et déséquilibrée ; ii) un dispositif de chauffage de fluide au défilé