COMSOL Multiphysics® Simulation of Energy Conversion and Storage Concepts Based on Oxide Crystals - new
C. Cherkouk, M. Zschornak, J. Hanzig, M. Nentwich, F. Meutzner, M. Urena, T. Leisegang, D. C. Meyer
Institute of Experimental Physics, Technische Universität Bergakademie, Freiberg, Germany
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 ...
G. Minton , R. Purkayastha , S. Walus , M. Marinescu , T. Zhang , G. Offer ,
 Oxis Energy Ltd, Oxford, United Kingdom
 Imperial College London, London, United Kingdom
During the basic operation of a lithium-sulfur (Li-S) cell, sulfur molecules are required to undergo a complex mix of electrochemical and chemical reaction processes. To date, almost all modeling of Li-S cell behavior has been undertaken using electroneutral, structurally homogenized, cell scale models accounting for most of these processes. The presented work was undertaken in order to try and ...
向斌 , 江露 , 周洋 , 王佳宁 
引言：钢结构设备的防腐保护主要采用阴极保护和涂层保护。其中，涂层保护除了防腐同时具备防红外、降温等特殊性能。 此次模拟，通过 COMSOL Multiphysics® 模拟设备在裸钢和 SiO2@ATO 涂层状态下的表面电位分布，证实了 SiO2@ATO 涂层的防腐性和抗红外及降温性能，并验证了 COMSOL Multiphysics® 数值模拟碳钢腐蚀表面电位分布的可靠性。 模拟过程中，假设电解质电导率为常数，阳极的各参数（尺寸、成分、分布等）保持不变。 计算方法：使用“二次电流分布”接口描述电极反应，“稀物质传递”接口描述亚铁离子输运，采用瞬态研究。参数： 1）温度 T； 2）电解质电导率 σ； 3）阴、阳极平衡电位 E_a、E_c； 4）阴、阳极交换电流密度 i0_c、i0_a； 5）传递系数 α 和 β； 6）初始时刻的亚铁离子浓度； 7）亚铁离子在硫酸溶液中扩散系数。 结果 ...
P. Ghods, K. Karadakis, O. B. Isgor, and G. McRae
Carleton University, Ottawa, Ontario, Canada
Corrosion of rebar in concrete is one of the most prominent durability problems in reinforced concrete, especially where de-icing or seawater salts come into contact with the structures. Previous electrochemical and microscopic investigations have shown that local crevices between the mill scale and the underlying steel surface accelerate the corrosion initiation of rebar in concrete. Steel ...
Kinetic Investigation of a Mechanism for Generating Microstructures on Polycrystalline Substrates Using an Electroplating Process
T. Soares, H. Mozaffari, H. Reinecke
Universität Freiburg, Freiburg im Breisgau, BW, Germany
Hochschule Furtwangen, Tuttlingen, BW, Germany
The purpose of this study is to understand the growth mechanism of copper (Cu) films on a Cu-Zn system substrate with a pre-defined pattern. The pattern was defined by conducting a selective etching process on a two-phase polycrystalline substrate. As a result of this process, there were etched regions correspondent to beta-phase crystals and quasi non-etched regions that belong to alpha-phase ...
Geraint Minton , Rajlakshmi Purkayastha , Laura O’Neill , Sylwia Walus , Mark Wild , Monica Marinescu , Teng Zhang , Gregory Offer ,
 Oxis Energy Ltd, Abingdon, Oxfordshire, UK
 Mechanical Engineering Department, Imperial College, London, UK
Lithium-sulphur (Li-S) batteries have the potential to surpass the energy storage capability of Li-ion batteries due to their high theoretical gravimetric energy density of 2700 Wh/kg. However, the processes which drive the system behaviour are much more complex than those in a Li-ion cell, meaning that controlling them to realise energy densities much above 350 Wh/kg is challenging. In a Li ...
F. A. Daniels, D. J. L. Brett, A. R. Kucernak, and C. Attingre
University College London, London, UK
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 ...
Renewable Energy RD Center, Chung-Hsin Electric & Machinery, Taiwan
Proton exchange membrane fuel cells (PEMFCs) were investigated using COMSOL Multiphysics with the AC/DC Module and Chemical Engineering Module. Simulation may be used to increase the performance while decreasing the cost of the catalyst later (CL). Experimental validation of single and multi-layer CL was performed for varied PBI electrolyte content. The validated model was used to investigate ...
Transient Modelling of a Fluorine Electrolysis Cell; Fully Coupled Electric Currents, Heat-Transfer, Diluted Species Transport and Laminar Bubbly Flow
R. Pretorius, P. L. Crouse, and C. J. Hattingh
University of Pretoria, Pretoria, Gauteng, South Africa
Metallurgical Testing and Consultation (MTC) cc, Farrarmere, South Africa
A laboratory-scale fluorine reactor was simulated with COMSOL Multiphysics®. This model employs fundamental fully coupled electron-, heat-, mass- and momentum transfer (two-phase) equations to deliver a transient model of the above-mentioned reactor. Quasi-steady-state results were produced for the current density, electric field, temperature, reactive species concentration, gas- and liquid ...
Modeling a Non-Flooding Hybrid Polymer Electrolyte Fuel Cell and Related Diffusion-Migration-Reaction Systems
B.E. McNealy, J.L. Hertz
University of Delaware, Newark, DE, USA
Introduction: Understanding the mass and charge transport behavior of heterogeneous systems that include diffusion, migration, and reaction of ions is important in fuel cells, batteries, and other electrochemical applications. Here, a numerical model for charged species transport and reaction has been developed to simulate the electrochemical behavior of a novel type of “non-flooding” hybrid ...