Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Improving the Sensoring of PEM Fuel Cell by Numerical Techniques - new

S. Skoda[1], E. Robalinho[2], E. F. Cunha[1], M. Linardi[1]
[1]Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP, São Paulo, SP, Brazil
[2]Universidade Nove de Julho - UNINOVE, São Paulo, SP, Brazil

The use of numerical techniques in PEM fuel cell sensoring represents an advantage of project engineering, reducing the costs and accelerating the manufacturing of prototypes. In this work some numerical responses are shown, relating to numerical sensoring of water and oxygen mole fractions at cathode of a 5 cm² of geometric area PEM fuel cell. The need to recognize a geometric figure of merit ...

Simulation of a Heated Tool System for Jet Electrochemical Machining

M. Hackert[1], G. Meichsner[2], and A. Schubert[1][2]

[1]Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, Chemnitz, Germany
[2]Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz, Germany

Jet Electrochemical Machining (Jet-ECM) is an unconventional procedure using localized anodic dissolution for micromachining. An increasing of the electrolyte temperature will lead to an increase of the electrical conductivity of the electrolyte by about 30% and to a reduction of the dynamic viscosity of the electrolyte by about 25 %. Both will improve the process. Therefore a Jet-ECM tool ...

Modeling of the Material/Electrolyte Interface and the Electrical Current Generated During the Pulse Electrochemical Machining of Grey Cast Iron

O. Weber[1], A. Rebschläger[1], P. Steuer[1], D. Bähre[2]
[1]Center for Mechatronics and Automatization, Saarbrücken, Germany
[2]Institute of Production Engineering, Saarland University, Saarbrücken, Germany

The Pulse Electrochemical Machining is especially suitable for the precise production of complex geometric contours with high precision and high surface quality demands in series manufacturing. During this process, the negative structure of an electrode is copied to the workpiece without sub-surface damages. An adequate knowledge of the current and thus of the material removal behavior is ...

COMSOL Multiphysics® Simulation of Energy Conversion and Storage Concepts Based on Oxide Crystals - new

C. Cherkouk[1], M. Zschornak[1], J. Hanzig[1], M. Nentwich[1], F. Meutzner[1], M. Urena[1], T. Leisegang[2], D. C. Meyer[1]
[1]Institute of Experimental Physics, Technische Universität Bergakademie, Freiberg, Germany
[2]Fraunhofer-Technologiezentrum, Freiberg, Germany

A mathematical model based on a finite element method (FEM) is presented as an initial approach for a system converting waste heat energy into chemical energy. This system consists of a pyroelectric LiNbO3 plate placed into a cylinder which undergoes a laminar water flow with an appropriate periodic heat source. It solves the heat transfer equation in non-isothermal flow, where the density of ...

An Agglomerate Model for the Rationalisation of MCFC Cathode Degradation

B. Bozzini[1], S. Maci[1], I. Sgura[2], R. Lo Presti[3], and E. Simonetti[3]
[1]Dipartimento di Ingegneria dell’Innovazione, Università del Salento, Lecce, Italy
[2]Dipartimento di Matematica, Università del Salento, Lecce, Italy
[3]ENEA Casaccia, Dipartimento TER, Centro Ricerche Casaccia, S. Maria di Galeria, Roma, Italy

This paper describes the numerical modeling of a key material-stability issue within the realm of Molten Carbonate Fuel Cells (MCFC). The model describes the morphological and attending electrocatalytic evolution of porous NiO electrodes and is apt to predict electrochemical observables that can be recorded during Fuel Cell operation. The model has been validated with original experimental data ...

FEM Simulation of the Scanning Electrochemical Potential Microscopy (SECPM)

R. Hamou, P. Biedermann, M. Rohwerder, and A. Blumeneau
Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany

The present work focuses on modeling a new experimental technique: Scanning Electro-chemical Potential Microscopy (SECPM), which is used to probe the potential profile of the electric double layer (EDL). We used an electrostatic approach to compute the EDL potential measured within the metallic probe. Also, we investigated the effect of the interaction of the electrode/probe double layers on the ...

Simulation of Current Collector Corrosion Effects on the Efficiency of Molten Carbonate Fuel Cells

I. Sgura[1], F. Zarcone[2], and B. Bozzini[2]
[1]Dipartimento di Matematica, Università del Salento, Lecce, Italy
[2]Brindisi Fuel Cell Durability Laboratory, Facoltà di Ingegneria Industriale, Università del Salento, Brindisi, Italy

Corrosion and contact ohmic resistance of the stainless steel current collectors in molten carbonates is one of the greatest obstacles to widespread application of molten carbonate fuel cells (MCFC). We simulate the variation of material parameters values, accounting for the impact of corrosion of the metallic current collectors on the performance of the porous cathode. Furthermore, we couple a ...

Using Computational Multiphysics to Optimise Channel Design for a Novel PEM Fuel Cell Stack

F. A. Daniels[1], D. J. L. Brett[1], A. R. Kucernak[2], and C. Attingre[2]
[1]University College London, London, UK
[2]Imperial College London, London, UK

Polymer electrolyte membrane (PEM) fuel cells have significant potential as a source of clean, efficient energy production. This study presents a three-dimensional, non-isothermal, fully-coupled model of a PEM fuel cell with printed circuit board current collectors. The effect of the current collector design on transport phenomena and consequent cell performance is investigated. The model ...

Three-Dimensional Percolation Properties Simulation of a Marine Coating Based on Its Real Structure Obtained from Ptychographic X-Ray Tomography - new

B. Chen[1], M. Guizar-Sicairos[2], G. Xiong[1], L. Shemilt[1], A. Diaz[2], J. Nutter[1], N. Burdet[1], S. Huo[1], F. Vergeer[3], A. Burgess[4], I. Robinson[1]
[1]London Centre for Nanotechnology, University College London, London, UK
[2]Paul Scherrer Institute, Villigen, Switzerland
[3]AkzoNobel Co. Ltd., Sassenheim, Netherlands
[4]AkzoNobel (UK) Co. Ltd., Tyne and Wear, UK

We present quantitative nano-scale analysis of the 3D spatial structure of an anticorrosive aluminium epoxy barrier marine coating obtained by ptychographic X-ray computed tomography (PXCT) [1-3]. We then use COMSOL Multiphysics® software to perform simulations on the acquired real 3D structure to demonstrate how percolation through this actual 3D structure impedes ion diffusion in the ...

Influence of Electrode Kinetics on Lithium-ion Battery Characteristics

H. Machrafi[1,2], S. Cavadias[2]
[1]University of Liège, Thermodynamics of Irreversible Phenomena, Liège, Belgium
[2]University Pierre et Marie Curie, Laboratoire des Procédés Plasma et Traitement de Surface, Paris, France

The purpose of this work is to show whether an important difference in Lithium solid concentration and electrolyte concentration can be observed in a Lithium-ion battery model, when considering either the Butler-Volmer kinetics or the Tafel kinetics for describing the electrode kinetics (including a boundary layer between the electrolyte and the electrode particles). During discharge, the ...