周川冀越 , 王贵欣, 朱铧丞,
锂空电池中空气电极是阴极反应的重要场所，空气电极结构设计的好坏极大地影响了锂空气电池的能量效率、倍率性能和循环寿命。为了强化氧气在空气电极中的传递过程，本文对一种层级结构空气电极进行研究：由泡沫铝制成的氧气分布板承载排列有序的碳纳米管阵列，氧气在阵列管中有规律传输、排布、反应。经计算得模拟计算所需的阵列管规格为外径1200、1400、1600nm;管长35000、43000、49000nm。然后绘制出9组数据的空气电极层级结构三维图纸，导入 COMSOL Multiphysics 5.2a 中，运用多孔介质稀物质接口，定义材料后编译域和边界条件，完成网格划分后进行后处理，最终模拟出氧气在空气电极内部传递过程与达到稳态后的氧气分布结果。接着用得到的数据在 Origin 绘图软件上绘制二维与三维柱状图，比较九组数据，发现规格为内径 1300nm ,管长 35000nm ,长径比为 21 ...
M. Suárez , and F. Samaniego 
Faculty of Sciences, Michoacán University (UMSNH), Morelia, Michoacan, Mexico
Faculty of Engineering Postgrade Studies Division, National University of Mexico (UNAM), Mexico City, Mexico
New geothermal energy sources hold promise for the future. Deep submarine geothermal energy related to hydrothermal vents is emerging in many places along the oceanic spreading centers. Shallow submarine geothermal systems are found near to continental platforms. We present the initial development of mathematical models to simulate the energy transport in submarine systems. A model for the ...
HAWK, Fachhochschule Hildesheim/Holzminden/Göttingen, Germany
In this paper resonances in tapered double-port TEM waveguides are used as benchmark for simulations. FEM simulations with COMSOL Multiphysics® and simulations using generalised telegraphist's equations with MATLAB® are compared to ananalytical method capable of calculating the resonances of higher order modes. It is valid for tapered double-port TEM waveguides with constant ...
D. Scandura, G. Currenti, and C. Del Negro
Istituto Nazionale di Geofisica e Vulcanologia Sezione di Catania, Catania, Italy
In volcanic areas, the presence of heterogeneous materials and high temperatures affect the rheological behaviour of the Earth's crust that calls for considering the anelastic properties of the medium surrounding the magmatic sources. A thermo-mechanical numerical model is performed for evaluating the temperature dependency of the elasto-plastic solution. Both temperature distributions and ...
I. Borsi and A. Fasano
Dipartimento di Matematica U. Dini, Università di Firenze, Firenze, Italy
In this paper we present a model to describe the process of waste water filtration based on hollow-fibre membrane filters. In particular, we deal with membranes whose pores diameter is in the range 0.01-0.1 µm. The main problem in these filtering systems is the membrane fouling. The mathematical model consists in two equations for the Darcy's flow through the filter, coupled with an ...
Simulating the Influence of the Nozzle Diameter on the Shape of Micro Geometries Generated with Jet Electrochemical Machining
A. Schubert, M. Hackert, and G. Meichsner
Chair Micromanufacturing Technology, Faculty of Mechanical Engineering, Chemnitz University of Technology, Chemnitz, Germany
Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz, Germany
Jet Electrochemical Machining (Jet-ECM) is an unconventional procedure for micromachining. Based on localized anodic dissolution three-dimensional geometries and microstructured surfaces can be manufactured using Jet-ECM. COMSOL Multiphysics is used at Chemnitz UT to simulate the electric current density in the jet and the dissolution process. A mesh displacement dependent on the normal current ...
M. Quast and N.R. Lalic
Gunytronic GmbH, St Valentin, Germany
Corona discharge is used in several applications such as surface treatment of polymers, photocopying or dust removal in air conditioning. Streamer formation is undesirable for most of these applications. Therefore, several studies have been dedicated to investigate the formation and propagation of streamers, which are still not fully understood. The most suitable models to describe streamers are ...
COMSOL\'s new CFD Module has been tested for laminar and turbulent flows in simple geometries, with couple or segregated solver. These tests allow mesh sensitivities and comparison with analytical solutions. They also give a first idea of cpu time and RAM use for standard cases. In a second part a thermal-fluid simulation of a real industrial application is done: the air flows cooling a large ...
G. Rádi, T. Varga, and T. Chován
University of Pannonia, Veszprem, Hungary
Nowadays mathematical models are applied in almost every field of our life to predict how real systems behave. Computational Fluid Dynamics (CFD) has become a standard tool for analyzing various situations where fluid flow has a significant effect on the studied processes. Complex models can be implemented and solved in commercial CFD packages (e.g. COMSOL Multiphysics). The goal of this paper ...
J. Orjuela, and A. González
Dept. de Ingeniería Química Facultad de Ingeniería
Universidad de los Andes
A bidimensional and pseudo homogenous model was proposed for the study of mass transfer in the bioadsorption process of chromium VI in the S-layer of immobilized Bacillus sphaericus in a packed column. The implementation of such a model in COMSOL Multiphysics will be explained in detail and the final results presented. These include chromium concentration profiles along the column and its ...