Artigos Técnicos e Apresentações

Aqui você encontrará apresentações realizadas nas Conferências de Usuários COMSOL de todo o mundo. As apresentações englobam pesquisas e produtos inovadores feitas por engenheiros e cientistas usando o COMSOL Multiphysics. Os tópicos abramgem uma grande gama de indústrias e aplicações, como elétrica, mecânica, escoamento e química. Use a função de busca "Quick Search" para encontrar apresentações na sua área de interesse.

Advanced Multiphysics Actuation Model of Ionic Polymer-Metal Composites

D. Pugal[1], K. Kim[1], and A. Aabloo[2]
[1]ME Department, University of Nevada Reno, Reno, NV
[2]University of Tartu, Tartu, Estonia

Modeling electromechanical actuation of ionic polymer-metal composite (IPMC) material is considered in this work. Ionic current in the polymer is described with the Poisson-Nernst-Planck system of equations. Calculated ionic concentration is related to the deformation of the material. To include the effect of the electrodes, the ionic current and the electric current in the electrode domains is ...

Simulating Frequency Nonlinearities in Quartz Resonators at High Temperature and Pressure

A. Beerwinkle[1], R. Singh[1], and G. Kirikera[2]
[1]Mechanics of Advanced Materials Laboratory, School of Mechanical and Aerospace Engineering, Oklahoma State University, Tulsa, OK
[2]Geophysical Research Company, LLC, (GRC) Tulsa, OK

A three-dimensional finite element model, based on the linear field equations for superimposed small vibrations onto nonlinear thermoelastic stressed media given by Lee and Yong, was developed. This method involves solving the thermal stress and piezoelectric model with geometric and material nonlinearities. The thickness-shear mode frequency response of the model was benchmarked to ...

HIIPER Space Propulsion for Future Space Missions

G. H. Miley[1], M. P. Reilly[2], B. Ulmen[3], P. Keutelian[3], and J. Orcutt[3]
[1]NPL Associates, Inc., Urbana-Champaign, IL
[2]Starfire Industries, Champaign, IL
[3]University of Illinois, Urbana-Champaign, IL

A coupled helicon/IEC plasma jet is in development for space propulsion applications. This device decouples the ionization and plasma acceleration process into separate stages. A realistic model is to consider a plasma media where the relative permittivity is negative or imaginary. Toward this end, COMSOL readily considers complex permittivity values, enabling a first attempt at modeling a ...

High Field Magnetic Diffusion into Nonlinear Ferrimagnetic Materials

J-W. Braxton Bragg[1], J. Dickens[1], A. Neuber[1], and K. Long[2]
[1]Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, TX
[2]Dept. of Mathematics, Texas Tech University, Lubbock, TX

Ferrimagnetic based, coaxial nonlinear transmission lines (NLTLs) provide a means to generate sub-nanosecond risetime pulses (from nano-second input pulses) or megawatt level high power microwave oscillations, depending on the geometry, material, and external bias fields. This investigation uses the commercially available, finite element solver COMSOL to provide insight into pulse behavior. ...

Simulation Studies on Stress Generation and Volume Expansion due to Electrochemical Lithium Insertion in a Silicon Nanowire

G. Sikha, and J. Gordon
Applied Materials, Inc.
Santa Clara, CA

Silicon electrodes are presently being pursued as the potential negative electrode for lithium-ion batteries owing to its high gravimetric (mAh/g) and volumetric capacity (mAh/L) compared to the existing state of the art graphite electrode. Recent experimental studies have demonstrated the use of nano size Si electrodes which minimizes insertion induced stresses due to facile strain ...

Designing Materials for Mechanical Invisibility Cloaks

P. Olsson[1], F. Larsson[1], A. Khlopotin[1], S. Razanica[1]
[1]Chalmers University of Technology, Gothenburg, Sweden

In solid mechanics, there is considerable interest in achieving “invisibility”. The applications in mechanics include protection of structures and parts of structures from potentially harmful transient waves and steady state vibrations. A suggested large scale application is that protection against seismic waves from earthquakes could be achieved by using cloaking to re-route the waves around ...

Perforation Effect on a Rectangular Metal Hydride Tank for Hydriding and Dehydriding Process

E. Gkanas[1][2], S. Makridis[1][2], E. Kikkinides[1], A. Stubos[2]
[1]Department of Mechanical Engineering, University of Western Macedonia, Kozani, Greece
[2]Environmental Laboratory, Institute of Nuclear Technology and Radiation Protection, NCSR 'Demokritos', Agia Paraskevi, Athens, Greece

Hydrogen storage in a metal hydride bed, uses an intermetallic alloy that can absorb efficiently high amounts of hydrogen by chemical bonding resulting to metal hydrides. This alloy is capable of absorbing and desorbing hydrogen while maintaining its own structure. The heat, mass and momentum transfer in a metal-hydride reactor is mathematically described by energy, mass and momentum balance ...

3D Modeling of Urban Areas for Built Environment Applications Using COMSOL

J. van Schijndel[1]
[1]Eindhoven University of Technology, Eindhoven, The Netherlands

This paper presents the modeling and simulation results of wind velocities in urban areas. The main idea was to build random generated urban areas for studying the influence of different urban geometries, from relative open to more dense, on wind profiles. The Spalert-Allmaras turbulent flow model turned out to be suitable for domains up to 50 x 50 x 100 m^3. The k-? turbulence model provided ...

Calculations of the FMR Spectrum in 1D Magnonic Crystals

M. Mruczkiewicz[1], M. Krawczyk[1], V.K. Sakharov[2], Yu. V. Khivintsev[2], Yu. A. Filimonov[2], S. A. Nikitov[3]
[1]Nanomaterials Physics Division, Faculty of Physics, Adam Mickiewicz University, Pozna?, Poland
[2]Kotel’nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences (Saratov Branch), Saratov, Russia; Laboratory “Metamaterials”, Chernyshevsky Saratov State University, Saratov, Russia
[3]Kotel’nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Moscow, Russia; Laboratory “Metamaterials”, Chernyshevsky Saratov State University, Saratov, Russia

FMR spectra of the periodic microstructures (one-dimensional magnonic crystals, 1D MCs) were obtained using COMSOL with use partial differential equation interface. Results of these calculations were successfully compared with an experimental data for Damon-Eshbach (DE) and Backward-Volume (BV) geometries. The presented tool allows to analyze periodic structures with various geometries and ...

Aggregation Kinetics of Colloidal Nanoparticles in a Circulating Microfluidic Cavity

M.R. Barmi[1], B.D. Piorek[1], M. Moskovits[2], C.D. Meinhart[1]
[1]Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, CA, USA
[2]Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA, USA

Pressure-driven air flow is directed over the microfluidic cavity induces circulating fluid motion in the cavity. Analyte contained in the air stream is absorbed into the cavity, mixes with the nanoparticles as a result of the circulating cavity flow. Therefore, the nanoparticles sequentially aggregate into clusters of higher orders. The model captures: fluid dynamics of the air flow and ...

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