COMSOL Multiphysics for Efficient Solution of a Transient Reaction-Diffusion System with Fast Reaction
M.K. Gobbert, A. Churchill, G. Wang, and T.I. Seidman
Department of Mathematics and Statistics, University of Maryland, Baltimore County, Baltimore, Maryland, USA
A reaction between chemical species is modeled by a particular reaction pathway, in which one reaction is very fast relative to the other one. The diffusion controlled reactions of these species together with a reaction intermediate are described by a system of three transient reaction diffusion equations over a two-dimensional spatial domain. In the asymptotic limit of the reaction parameter ...
Department of Mechanical Engineering, University of Washington, Seattle, Washington, USA
A comparison of the commercial code COMSOL is performed with the bench-mark solutions provided by the literature for a tall, differentially heated rectangular cavity for aspect ratios of 8, 15, 20, and 33. At small Rayleigh numbers the flow is dominated by conduction. As the Rayleigh number is increased the flow becomes unstable, first resulting in multicellular secondary flow patterns, and then ...
P. Schmitz, A. Cockx, S. Geoffroy, and J. Gunther
Biochemical Engineering Dpt., Université de Toulouse, Toulouse, France
Chemical Engineering Dpt., Université de Toulouse, Toulouse, France
Mechanical Engineering Dpt., Université de Toulouse, Toulouse, France
An undergraduate course is developed to initiate future engineers to multiphysics numerical simulation by approaching concrete cases in various fields such as: heat transfers, fluid flow, mechanics, chemistry and electrostatics. The so called “Virtual Experiments” course consists of four projects given successively to students. Each project lasts about ten hours. The major notions related to ...
Mads Jakob Herring Jensen
Dr., Widex A/S, Denmark
In modern hearing aids, the performance of directional microphone systems is dependent on both the acoustics around thehearing aid and on the specific signal processing algorithms. The sound pressure at the microphone inlets depends on microphone location in the hearing-aid shell, the inlet shape, and on the placement of the hearing aid on the head of the user. In the present work, the ...
Dynamic Observation of Magnetic Particles in Continuous Flow Devices by Tunneling Magnetoresistance Sensors
A. Weddemann, A. Auge, F. Wittbracht, C. Albon, and A. Hütten
Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, Bielefeld, Germany
Dynamic measurement of magnetic particles in continuous flow devices is made very difficult by the limitations imposed by the sensors themselves. Thus, certain sensor layouts are restricted to either number sensitive or spatial resolutive measurements of magnetic particles. We investigate different new strategies to increase the detection threshold and introduce designs accomplishing both: ...
B. Boulbène, J. Morchain, and P. Schmitz
Université de Toulouse, NSA, UPS, INP, LISBP, Toulouse, France
We present numerical results involving microorganisms adhering to a plane surface submitted to a shear flow. The purpose is to have a better understanding of the removal mechanisms occurring during the cleaning in place of food processing equipments. The biological cell, i.e. the microorganism, is modelled as a rigid obstacle embedded in the bottom wall of the fluid domain. Shear induced ...
A. Coll, V. Di Virgilio, S. Bermejo, and L. Castañer
Universitat Politècnica de Catalunya, Barcelona, Spain
Photonic crystals are widely used in optical applications as waveguides and band filters. Filling the periodic structural material of photonic crystals with other materials is very useful in order to change the optical properties of the devices. In this paper electrostatic COMSOL simulations describing an electrospray deposition of particles in macroporous structures are performed.
V-M. Pulkkanen, and M. Olin
VTT Technical Research Centre of Finland, Espoo, Finland
A compacted bentonite clay buffer is planned to be used as a part of the engineered barrier system in the KBS-3 concept for the disposal of spent nuclear fuel. Simulations together with experimental studies are needed to ensure that bentonite fulfills its safety functions in the concept. In this paper, one type of bentonite model, namely a thermomechanical model developed by Jussila, is ...
A. Methlouthi, O. Rouaud, and L. Boillereaux
Industrial microwave ovens are widely used in agri-food and chemical applications. Resonant cavities are used to speed up chemical reactions and have the advantage to be small sized and efficient in terms of microwave distribution. These multimode cavities are considered as batch ovens where a small amount of products is treated. Rotating plates are added in the cavities to ensure a homogeneous ...
A.Torrents, N. Godino, F.J. del Campo, F.X. Muñoz, and J. Mas
Universitat Autònoma de Barcelona, Spain
Microbia Fuel Cells (MFC’s) are complex environments where electrochemical, physical and biological aspects must be considered together. In this work we present a 1D model partially describing a Shewanella oneidensis MFC that degrade sodium lactate [lactate -> Acetate + CO2 + 2H+ + 2e-]. The model, simulated using COMSOL, focuses on pH implications of the MFC operation. Release of protons during ...