Q. Zhang, Y. Liu, and S. Chen
Wuhan University, College of Chemistry and Molecular Science, Wuhan, China
COMSOL Multiphysics is a very helpful simulation software in our researches on both PEMFC and nanometer-sized electrodes. In the first part of our presentation, the influence of humidity and temperature to the performance of PEMFC are studied by simulating the MEA (membrane electrode assembly) in PEMFC. In the second part, models of different nanometer-sized electrodes, including spherical ...
R. Cumeras, I. Gràcia, E. Figueras, L. Fonseca, J. Santander, M. Salleras, C. Calaza, N. Sabaté, and C. Cané
Instituto de Microelectrónica de Barcelona, Barcelona, Spain
A micro Planar Ion Mobility Spectrometer (P-FAIMS) has been simulated using multiphysics software. In P-FAIMS target ions are discriminated by the application of the proper separation voltages to the electrodes of the system. Modelling of vapour phase ions of two compounds have been studied for different values of electric field amplitude to gas number density (E/N) ratio: a health risky volatile ...
G. Selembo, P. Selembo, J. Stanton, and G. Paulsen
University of North Carolina
Surface aeration systems are used in the wastewater treatment industry for the transfer of oxygen in the activated sludge process. These systems are capital intensive and also require a significant amount of energy to operate. Scale-up and design of these systems is largely empirical, and due to the size of these systems, modifications for experimental testing can be economically prohibitive. ...
V. Nicolas, C. Doursat, D. Grenier, T. Lucas, D. Flick
Institut de recherche en sciences et technologies pour l'environnement et l'agriculture, Rennes, France
AgroParisTech, UMR1145 Ingénierie Procédés Aliments, Massy, France
Bread is a food product which various complex physico-chemical phenomena occur during the cooking process. Thus, phenomena of heat and mass transfer are coupled to the deformation. In addition, bread is a multiphase product (solid, liquid and vapor) and composed of various components (dry matter, water, air and carbon dioxide). A 2D model is developed with COMSOL Multiphysics® 4.3b witch ...
C. F. Gomez, R. Schunk, R. F. Coker, J. Knox
NASA Marshall Space Flight Center, Huntsville, AL, USA
The objective of this simulation effort is to develop a mathematical model of vacuum desorption on a POC (Proof of Concept) canister loaded with Zeolite 13X/5A . This canister contains a pelletized adsorption bed which is used to adsorb H2O and CO2. Once this bed is fully saturated with an equilibrium loading, desorption is then accomplished by reducing the pressure to near vacuum. This type of ...
R. Inglés, J. Pallares, J.L. Ramirez, and E. Llobet
Dept. of Electronic, Electrical and Automatic Control Engineering, Universitat Rovira i Virgili, Tarragona, Spain
Department of Mechanical Engineering School of Chemical
Engineering Universitat Rovira i Virgili, Tarragona, Spain
We use finite elements simulations in order to study the fluid flow behavior in a chamber of a preconcentrator. We realized that most part of the fluid does not affect our preconcentrator because it is going out the chamber at high distance above it and parallel to the preconcentrator. So, we are wasting most part of our fluid and we need a lot of time to have a good concentrator factor. We ...
Simulations of Scanning Electrochemical Microscopy Experiments in Pure Negative and Positive Feedback Mode with Ring Microelectrodes
J. Mauzeroll, M. Mayoral, and D. Fabre
Department of Chemistry, Université du Québec à Montréal, Montreal, Quebec, Canada
Scanning electrochemical microscopy (SECM) is a powerful tool recently developed for studying structures and processes in micrometer and submicrometer sized systems. It can probe electron, ion, and molecule transfers, and other reactions at solid-liquid, and liquid-liquid, interfaces . This versatility allows for the investigation of a wide variety of processes, from metal corrosion to metabolism ...
G. Jovonavic, J. Jones, and A. Yokochi
School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, Oregon, USA
This paper describes the benefits of computational fluid dynamics in the development of a microreactor used in the desulfurization of aromatic compounds. It is crucial to verify diffusion and extinction coefficients to ensure accurate simulation results prior to experiments. COMSOL Multiphysics was used to model the behavior of all of the possible species present and reactions that may occur.
P. Buttin, B. Malki, P. Barberis, and B. Baroux
SIMAP/groupe SIR, CNRS, France
AREVA - AREVA NP - CEZUS Research Center, France
This paper studies multicomponent transport through zirconia, assuming a chemical reaction involving electrons and oxygen vacancies defects. Classically, according to the Wagner theory for ambipolar diffusion, the electroneutrality condition in the oxide is considered. Therefore three constraints must be satisfied on the transport problem: oxide stoichiometry, electroneutrality and the source ...
D. Hu, F. Zhang, H. Zhou, and J. Shao
LML, UMR8107, CNRS, University of Lille I, Lille, France
School of Civil Engineering and Architecture, Hubei University of Technology, Wuhan, China
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, China
A lixiviation-mechanical coupled model is developed for fiber reinforced concrete within this framework; both the influence of chemical degradation on short and long term mechanical behavior and the influence of mechanical loading on the diffusion coefficient can be considered. The elastic mechanical properties are written as function of chemical damage. A Drucker–Prager typed criterion with ...