Ici vous trouverez les présentations issues des Conférences COMSOL à travers le monde. Réalisées par des utilisateurs de COMSOL Multiphysics, ces présentations explorent tous les domaines actuels d'innovation. Les applications couvrent pratiquement tous les secteurs industriels et impliquent des phénomènes électriques, mécaniques, fluidiques et chimiques. Utilisez la recherche rapide pour trouver les présentations les plus intéressantes dans votre domaine d'intérêt.

Simulating Corrosion in a Crevice of Commercial Pure Titanium

G. Zhang [1, 2, 3],
[1] Department of Bioengineering, Clemson University, Clemson, SC, USA
[2] Department of Electrical and Computer Engineering, Clemson, SC, USA
[3] Institute for Biological Interfaces of Engineering, Clemson University, Clemson, SC, USA

Implant devices are assistive devices surgically placed in the human body to restore the functionality of organs and tissues. Metallic implants are often used for load bearing applications including the hip and knee joints. To allow maximum flexibility during surgery for surgeons to pick and choose different combinations of parts (say, head, neck and stem, in the case of total hip replacement), ...

Influence of pH and Carbonate Buffering on the Performance of a Lactate Microbial Fuel Cell

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 ...

Simulation of Deformed Solid Particles in Constrained Microfluidic Channel

M. Cartas-Ayala[1], R. Karnik[1]
[1]Massachusetts Institute of Technology, Cambridge, MA, USA

Characterization of particles has numerous applications in science and diagnostics. Recently, particle passage through constrained microchannels has been proposed to characterize particles based on their passage velocity. Nevertheless, there is no clear understanding of how the physics in this system interact. Here we quantify the effects of the flow around the particle by simulating the passage ...

Multiphysics Modeling of Electrode-Driven Renal Denervation for Hypertension Treatment - new

M. Miliani[1], F. Piccagli[1], C. Silvestro[1]
[1]Medtronic Invatec S.p.A., Roncadelle, Italy

Introduction: Chronic arterial hypertension (HTN) is a pathological condition characterized by prolonged high level of arterial blood pressure causing major damages to several human body apparata. Renal sympathetic denervation (RDN) has been found to effectively reduce systemic blood pressure. Metallic electrodes can be placed on an endovascular device connected to external radio frequency (RF) ...

Modeling Bacterial Transport and Removal in a Constructed Wetland System

E. Engström, B. Balfors, and R. Thunvik
Royal Institute of Technology, Stockholm, Sweden

In this study we evaluate transport, retention and subsistence of Escherichia coli (E. coli), a common fecal indicator bacteria, in a model (2x1m) of a constructed wetland. Transport occurs in the unsaturated and saturated zone. Inactivation is accounted for as a kinetic first-order process. Retention is assumed to be dominated by solid-air-water interface straining and is modeled with a kinetic ...

Updated Results of Singlet Oxygen Modeling Incorporating Local Vascular Diffusion for PDT - new

R. Penjweini[1], M. M. Kim[1], T. C. Zhu[1]
[1]Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA

Introduction: Singlet oxygen (¹O₂) has a critical role in the cell-killing mechanism of photodynamic therapy (PDT). Therefore, in this study, the distance-dependent reacted ¹O₂ is numerically calculated using finite-element method (FEM). Herein, we use a model [Ref. 1] that has been previously developed to incorporate the diffusion equation for the light transport in tissue and the macroscopic ...

On the Influence of Cancellous Bone Structure upon the Electric Field Distribution of Electrostimulative Implants - new

U. Zimmermann[1], R.Bader[2], U. van Rienen[1]
[1]Institute of General Electrical Engineering, University of Rostock, Rostock, Germany
[2]Department of Orthopaedics, University Medicine Rostock, Rostock, Germany

Since the 1980s, the accelerating effect of electromagnetic fields on bone regeneration is used to treat complicated fractures and bone diseases. At the University of Rostock, an electrostimulative hip revision system is developed, basing on the method of Kraus-Lechner. This method requires an electric fields between 5 and 70 V/m. The bone used for the simulations consisted of two homogenous ...

Effect of Permeability Diminution in Nutrient Diffusion in Intervertebral Disc

M. A. Chetoui [1], O. Boiron [2], A. Dogui [3], V. Deplano [2],
[1] Université de Monastir, Ecole Nationale D'ingénieurs de Monastir; Ecole centrale Marseille, Marseille, France
[2] Aix-Marseille Université, CNRS, Ecole Centrale, Marseille, France
[3] Université de Monastir, Ecole Nationale D'ingénieurs de Monastir, Marseille, France

Intervertebral discs (IVD) are fibro-cartilages situated between vertebrae providing their joint flexibility. They play a major role in the transmission and absorption of load through the spine. The disc can undergo progressive structural and quantitative changes in its composition and morphology related to mechanical load applied to the spine which can lead to disc degeneration; this disease is ...

Passive and Active Deformation Processes of 3D Fibre-Reinforced Caricatures of Cardiovascular Tissues

A. Di Carlo[1], P. Nardinocchi[2], T. Svaton[3], and L. Teresi[1]

[1]Modelling and Simulation Lab, Università Roma Tre, Roma, Italy
[2]Dept. of Structural & Geotechnical Engineering, Università di Roma La Sapienza, Roma, Italy
[3]Dept. of Mathematics, University of West Bohemia, Pilsen, Czech Republic

In this paper, we present a mathematical model of contractile elastic solids meant to simulate various districts of the cardiovascular system, and based on the concepts of active deformation and embedded muscle fibres. Specifically, here we deal with the modeling of the gross mechanics of the Left Ventricle (LV) which is strictly related to its pump function. As is well known, the effectiveness ...

Prediction of Time of Death Using a Heat Transport Model

J.L. Smart[1], and M. Kaliszan[2]
[1]University of Kentucky, Paducah, KY, USA
[2]Medical University of Gdansk, Gdansk, Poland

COMSOL Multiphysics® 4.0 was used to study conductive and convective heat transfer from the human eyeball to the surrounding air. Postmortem temperature decay curves were collected in eyeballs of numerous human corpses. Of course, these curves represent only a portion of the complete temperature decay curve, since the pathologist is able to start collecting temperature data only after some ...