E. Amores Vera, J. Rodríguez Ruiz
Centro Nacional del Hidrógeno, Puertollano, Spain
One of the most critical aspects on water electrolysis is gas-liquid separation, especially in systems with forced convection. The main problem of this kind of circulation is that a gas fraction could return to the electrolysis circuit. A suitable design of separator devices could be a solution in order to avoid a gas return to the electrolysis circuit. In this sense, the use of deflectors might ...
M.S. Nesro, I.M. Elfadel
Masdar Institute of Science and Technology, Masdar City, Abu Dhabi, UAE
Lithium microbatteries are replacing conventional power sources in many microsystems areas such as wireless sensors and biomedical monitors. In many of these applications, compact models of micro batteries are needed both at the microsystems design stage and at the real-time power management stage. These compact models are typically derived from physics-based discretized formulations. We have ...
F.T. Wandschneider, M. Küttinger, P. Fischer, K. Pinkwart, J. Tübke, H. Nirschl
Fraunhofer-Institute for Chemical Technology, Pfinztal, Germany
Karlsruhe Institute for Technology, Karlsruhe, Germany
A two-dimensional stationary model of a vanadium oxygen fuel cell is developed in COMSOL Multiphysics®. This energy storage device combines a vanadium flow battery anode and an oxygen fuel cell cathode. The oxygen reduction reaction generates additional water, leading to a degradation of the catalyst performance over time. A logistic function is introduced to the Butler-Volmer equation in order ...
COMSOL Multiphysics® Based Identification of Thermal Properties of Mesoporous Silicon by Pulsed Photothermal Method - new
N. Semmar, I. El Abdouni, A. Melhem
GREMI-UMR7344, CNRS/University of Orléans, Orléans, France
The silicon is mainly known under its single-crystal shape and polycrystalline. Since a few decades, a new type of morphology is developed: the porous silicon (p-Si). Meso-porous silicon (Mp-Si) is one of promising materials for future microelectronic chips multi-functionalization systems, and for micro-sensing devices. For thermal properties investigation many experimental systems were ...
University of Trinidad and Tobago, Couva, Trinidad and Tobago
This paper presents a 2D model of an intermediate temperature ammonia-fed SOFC (400 – 700 °C) based on the Temkin-Pyzhev model of ammonia decomposition. Phenomenological equations are implemented in COMSOL Multiphysics®. The Dusty Gas Model is used to model species transport in porous media, but a modification of Fick’s Law is used. Results show that intermediate temperatures can alleviate ...
R. Painter, S. Berryhill, L. Sharpe, S. K. Hargrove
Department of Civil Engineering, Tennessee State University, Nashville, TN, USA
Department of Mechanical Engineering, Tennessee State University, Nashville, TN, USA
COMSOL® "Single Particle Model for Lithium-Ion Batteries” (Model ID: 14527) is generalized to include an energy balance. This is accomplished by approximating the solution phase polarization as a function of current and temperature. The theoretical approach for this work is similar to Guo et al. [Journal of the Electrochemical Society, 158, (2) A122-A132 (2011)] for modeling lithium ion ...
The Effect of Electrolyte Flow Slots in Tooling Electrodes on Workpiece Surface Finish in Electrochemical Machining
Oregon State University, Corvallis, OR, USA
Electrochemical machining (ECM) uses electrolysis to precisely remove material at high rates. ECM has many advantages over conventional machining: no tool wear, no induced mechanical or thermal stresses, high removal rates virtually independent of material hardness or strength, and excellent surface finishes. However, challenges can arise during the design of the tooling electrode when ...
Analysis of the Electrochemical Removal of Aluminum Matrix Composites Using Multiphysics Simulation - new
M. Hackert-Oschätzchen, N.Lehnert, M. Kowalick, G. Meichsner, A. Schubert[1,2]
Professorship Micromanufacturing Technology, Technische Universität Chemnitz, Chemnitz, Germany
Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz, Germany
In the Collaborative Research Centre 692 at TU Chemnitz several academic institutions work on aluminum matrix composites (AMCs). These materials consist of an aluminum matrix, which is reinforced by SiC or Al2O3 particles with dimensions less or equal 1 µm. One main task is finishing machining of AMCs by electrochemical machining (ECM). The goals are depending on the application whether to ...
Screening Effects in Probing the Electric Double Layer by Scanning Electrochemical Potential Microscopy
R.F. Hamou, P.U. Biedermann, A. Erbe, and M. Rohwerder
Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf, Germany
A computational method is developed to study probing the electric double layer by Scanning Electrochemical Potential Microscopy. The model is based on a modified Poisson- Boltzmann equation, which takes into account steric effects. We investigated the effect of metallic apex protrusion and the Open Circuit Potential (OCP) of the tip on the probed potential. A clear electrostatic screening effect ...
Modeling of Liquid Water Distribution at Cathode Gas Flow Channels in Proton Exchange Membrane Fuel Cell – PEMFC
S. Skoda, E. Robalinho, A. Paulino, E.F. Cunha, M. Linardi
Instituto de Pesquisas Energéticas e Nucleares, São Paulo, Brazil
Universidade Nove de Julho, São Paulo, Brazil
The objective of this study is to determine the locations where liquid water accumulates at cathode gas flow channels, and the corresponding operating conditions. In such way it is possible to mitigate slug flow, responsible for channel blockage and hindering the diffusion of reactants to the catalytic sites. The model presented here is a comprehensive PEMFC 3D model, which includes liquid water ...