In questa sezione troverete i lavori presentati alle Conferenze mondiali COMSOL. Le presentazioni descrivono ricerche e prodotti innovativi progettati con COMSOL Multiphysics da colleghi di tutto il mondo. I temi delle ricerche presentate abbracciano un'ampia gamma di settori produttivi e aree applicative, in ambito elettrico, meccanico, fluidodinamico e chimico. Lo strumento di Ricerca Rapida vi permetterà di trovare le presentazioni che si riferiscono all'area di vostro interesse.

Chaotic Behavior of the Airflow in a Ventilated Room

A.W.M. van Schijndel[1]
[1]Eindhoven University of Technology, Eindhoven, The Netherlands

Chaotic systems may lead to instability, extreme sensitivity and performance reduction. Therefore it is unwanted in many cases. Due to these undesirable characteristics of chaos in practical systems, it is important to recognize such a chaotic behavior. The existence of chaos has been discovered in several areas during the last 30 years. However, there is a lack of studies in relation with ...

Multiphysics Simulations in Complex 3D Geometry of the High Flux Isotope Reactor Fuel Elements using COMSOL

J. Freels, and P. Jain
Oak Ridge National Laboratory
Oak Ridge, TN

A current research and development project is ongoing to convert the operating High Flux Isotope Reactor (HFIR) of Oak Ridge National Laboratory (ORNL) from highly-enriched uranium (HEU U3-O8) fuel to low-enriched uranium (LEU U-Mo) fuel. Because LEU HFIR-specific testing and experiments will be limited, we are relying on COMSOL to provide the needed multiphysics simulation capability to ...

Simulation of GMR in Granular C/Co Nanoparticles in Agarose - new

P. Hainke[1], D. Kappe[1], A. Hütten[1]
[1]Universität Bielefeld, Bielefeld, Germany

As the importance of nanoparticles is growing more and more, controlling and understanding the properties of nanoparticles became a focus of research. In this field Meyer at al. [1] are researching the GMR effect in granular gels to develop magnetoresistive sensors. The GMR in granular gels is simulated to investigate the physical processes in those systems. As soon as the models coincide with ...

Parameter Optimization for FEM Based Modeling of Singlet Oxygen During PDT Using COMSOL

T.C. Zhu, and X. Liang
University of Pennsylvania, Philadelphia, PA, USA

Singlet oxygen (1O2) is the major cytotoxic agent in photodynamic therapy (PDT). The reaction between 1O2 and tumor cells defines the treatment efficacy. Based on a previously developed model that incorporates the diffusion equation for the light transport in tissue and the macroscopic kinetic equations for the generation of the singlet oxygen, the distance-dependent reacted 1O2 is numerically ...

Solving the Paraxial Wave Equation using COMSOL

P. Mikulski, K. Mcilhany, and R. Malek-Madani
United States Naval Academy
Annapolis, MD

Here we present and discuss numerical solutions to the paraxial wave equation using COMSOL (2D, PDE, General Form, time-dependent analysis). Ultimately, the goal is to extend this treatment of free-space beam propagation to the case of propagation through a medium that is non-uniform and subject to non-linear effects where the beam itself is modifying the properties of the medium in which it is ...

COMSOL Implementation of Valet-Fert Model for CPP GMR devices

T. Xu[1], C.K.A. Mewes[1], S. Gupta[2], and W.H. Butler[1]
[1]Department of Physics and Astronomy and Center for Materials for Information Technology, University of Alabama, Tuscaloosa, Alabama, USA
[2]Department of Metallurgical and Materials Engineering and Center for Materials for Information Technology, University of Alabama, Tuscaloosa, Alabama, USA

The Giant Magneto Resistance (GMR) effect is a quantum mechanical effect which can be observed in systems consisting of thin alternating ferromagnetic and non-ferromagnetic layers. Simulation using COMSOL allows the evaluation of the magneto-resistance ratio and the electrical resistances of realistic CPP-GMR devices and opens the possibility to study new device materials and designs.

Hybrid FEM-BEM Approach for Two- and Three-Dimensional Open Boundary Magnetostatic Problems

A.Weddemann[1], D. Kappe[2], and A. Hütten[2]
[1]Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge MA, USA
[2]Department of Physics, Thin Films and Physics of Nanostructures, Bielefeld University, Bielefeld, Germany

In principal, the calculation of the magnetic state inside a magnetic object requires the evaluation of the field in the entire unbounded space. With finite element methods restricted to finite domains, commonly auxiliary domains are employed which result in a non-physical cut-off. Not only are these additional domains result in an increased number of degrees of freedom which are strictly ...

Numerical Simulation of Warm-Air Drying of Mexican Softwood (Pinus Pseudostrobus)

S. Sandoval Torres[1], E. Hernández-Bautista[1], J. Rodríguez-Ramírez[1], A. Carrillo Parra[2]
[1]Instituto Politécnico Nacional, CIIDIR, Oaxaca, Mexico
[2]Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León, Linares, N.L. México

In this work, the numerical simulation of Mexican softwood (Pinus pesudostrobus) drying is presented by solving a physics-based model. The model was developed by considering the heat and mass transport and the representative elementary volume, which involves the solid, liquid and gas phases. We solved a system of partial differential equations by numerical factorization in COMSOL Multiphysics 3 ...

Modeling the Collimator-Detector Scattering Using Stochastic Differential Equations and COMSOL

A. Jeremic[1], T. Farncombe[2], S. Liu[2], and Y. Abdul-Rehman[1]
[1]Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada
[2]Department of Radiology, McMaster University, Hamilton, Ontario, Canada

Single photon emission computed tomography (SPECT) is a nuclear medicine imaging technique that uses gamma rays. It has been especially useful for bone scans, cardiac perfusion imaging, tumor scans and brain imaging. The main advantage of SPECT imaging is that it can target particular tissue receptors allowing one to focus on the imaging of the diseased tissue. In most cases Monte Carlo ...

Looking for the Origin of Power Laws in Electric Field Assisted Tunneling

H. Cabrera[1], D.A. Zanin[1], L.G. De Pietro[1], A. Vindigni[1], U. Ramsperger[1], D. Pescia[1]
[1]Laboratory for Solid State Physics, ETH Zurich, Zurich, Switzerland

A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased ...