Computational Analysis of Transport Phenomena and Electrochemical Reactions in a Polymer-Electrolyte-Membrane Fuel Cell
P. Mina, J. Pauchet, and P. Schott
LITEN/DTH/LCPEM , CEA-Grenoble, Grenoble, France
A two-dimensional transient model for the membrane electrode assembly of a Polymer-Electrolyte-Membrane Fuel Cell is presented. Species and energy transport, electrical current distribution, and electrochemical kinetics are described in the computational domain, which consists of the electrolyte membrane as well as a gas diffusion layer, a micro-porous layer and a catalyst layer for both the ...
C. Siegel1,2, G. Bandlamudi1,2, and A. Heinzel1,2
1Zentrum für BrennstoffzellenTechnik (ZBT) GmbH, Duisburg, Germany
2Institut für Energie- und Umweltverfahrenstechnik, University of Duisburg-Essen, Duisburg, Germany
Phosphoric acid doped polybenzimidazole (PBI) membranes are commonly used for high temperature polymer-electrolyte-membrane (HTPEM) fuel cells in order to achieve high proton conductivity. Only a few numerical HTPEM fuel cell studies along with experimental validation are currently available. Here, a HTPEM fuel cell model is developed and simulated using COMSOL Multiphysics. Emphasis is put on ...
M. Hanke, and M. Cabauatan-Villanueva
School of Computer Science and Communication, Royal Institute of Technology, Stockholm, Sweden
The simulation of the metabolism in mammalian cells becomes a severe problem if spatial distributions must be taken into account. Especially the cytoplasma has a very complex geometric structure which cannot be handled by standard discretization techniques. In the present paper we propose a homogenization technique for computing effective diffusion constants. This is accomplished by using a ...
M. S. Virk, A. E. Holdø, and S. Kaennakham
Energy & Environmental Technology Applied Research Group, Faculty of Engineering and Computing, Coventry University, Coventry, UK
Microfluidic systems hold promise for many novel applications where rapid mixing is important, and has lead to a number of new developments. Despite such major developments, no systematic study has been carried out to understand the effect of flow mechanisms and geometry on microfluidic mixing. This work focuses on a mixing analysis of low Reynolds number (< 25) microfluids in a T-shaped passive ...
Modeling Signal Propagation in Integrated Graded Index Multimode Waveguides with the Finite Element Method
T. Kühler, and E. Griese
Institute of Theoretical Electrical Engineering and Photonics, Universität Siegen, Siegen, Germany
A novel approach for realizing electrical printed circuit boards with integrated optical interconnects for high bandwidth data transmission is the implementation of waveguides in thin glass foils which can be integrated into the PCB lamination composite. The application of an ion-exchange process results in local changes of the refractive index and finally graded index multimode waveguides are ...
Energy Engineering Department, Università degli Studi di Firenze, Firenze, Italy
The natural ventilation of buildings provides improvement of internal comfort and air quality conditions leading to a significant reduction of the consumption of cooling energy. In the present paper the air flow patterns, velocity and air temperature distributions inside a historical building in Palermo (Italy), at present used as a library, were investigated by a 3D transient simulation using ...
Coupled Electromagnetic, Thermal and Fluid Dynamics Simulation of Axial Flux PM Synchronous Machines
DAEIMI, Department of Automation, University of Cassino, Cassino, Italy
This paper investigates the Electromagnetic and thermal behavior of Synchronous Axial Flux Permanent Magnet Machines. The Axial Flux machine employed for tests and simulations has a Soft Magnetic Compound stator core. The electromagnetic analysis is used to assess electromechanical variables and machine parameters. Furthermore, the thermal source is obtained from a DC current flow model which is ...
M. Stroe1, R. Oltra1, B. Vuillemin1, and G. Girardin2
1Institut Carnot de Bourgogne (ICB), Dijon, France
2AREVA NP, France
Crevice corrosion of stainless steel in chloride media was investigated based on an 11 species model. The role of parameters such as pH inside the crevice, external potential, chloride concentration of the bulk solution and crevice geometry was studied. A thermodynamic criterion for arrest / propagation of the crevice corrosion was used in order to identify the conditions for which the localized ...
A. Bradji1, and E. Holzbecher2
1Charles University, Prague, Czech Republic
2Weierstrass Institute for Applied Analysis and Stochastics WIAS, Berlin, Germany
The convergence of numerical solutions is mainly determined by the convergence order, which quantifies the improvement of the solution when the mesh is refined. In this paper we examine various differential equations and the convergence behavior of their COMSOL Finite Element solutions. The numerically observed convergence rates are compared with theoretical results, as far as these are ...
J. Frassy1, C. Lecot2, M. Murariu3, C. Delattre1, and A. Soucemarianadin1
1Université Joseph Fourier, Grenoble, France
2Université de Savoie, Le Bourget-du-Lac, France
3LETI, CEA, Grenoble, France
We present simulations of drops spreading on random surfaces with either chemical or topographical heterogeneities. All the computations are made within the framework of the lubrication approximation. The droplet height is the solution of a time-dependent nonlinear fourth order partial differential equation, which is solved using COMSOL. Fast Fourier Transform (FFT) together with an appropriate ...