Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

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 ...

Stability Analysis of ALE-Methods for Advection-Diffusion Problems

A. Weddemann, and V. Thümmler
Bielefeld University, Germany

ALE-methods are frequently used to solve systems of partial differential equations (PDEs) on moving domains. The main idea of these methods is to incorporate the time evolution of the domain into the equations. However, the motion of the domain with respect to time induces convective fluxes in the resulting equations. These can lead to stability problems of the numerical method if they become ...

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 ...

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 that these additional domains result in an increased number of degrees of freedom which are strictly ...

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 ...

Cloud Computations for Acoustics with Coupled Physics - new

A. Daneryd[1], D. Ericsson[2]
[1]ABB Corporate Research, Västerås, Sweden
[2]COMSOL AB, Stockholm, Sweden

For certain classes of scientific and technical computations the cloud may offer easily accessible, scalable, and affordable gigantic computing power. A power that for these classes may lead to a step change in model and analysis complexity compared to what is feasible with dedicated clusters and similar networked solutions. Acoustics with or without interaction with coupled physics fields ...

Numerical Study of an LTD Stirling Engine with Porous Regenerator

N. Martaj[1], P. Rochelle[1][2], L. Grosu[1], R. Bennacer[3], and S. Savarese[4]
[1]Universitè de Paris, Paris, France
[2]Institut Jean Le Rond d'Alembert, Université Paris 6
[3]Laboratoire LEEVAM «Environnement, Energétique, Valorisation, Matériaux», Universitéde Cergy-Pontoise
[4]COMSOL France, 5 pl. R Schuman, 38000 Grenoble

The alternative engines of Stirling type, are engines running on "hot air", using both an external heat source and regeneration. They should be considered as an alternative for the effective conversion of renewable energy sources into work, with their theoretical yield equal to the theoretical Carnot limit. The output efficiency and the power of these engines are strongly related to the ...

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 ...

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.