Technical Papers and Presentations

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.

Explicit Dosimetry for Photodynamic Therapy; Singlet Oxygen Modeling based on Finite-Element Method

Ken Kang-Hsin Wang[1], and Timothy C. Zhu[1]
[1]Department of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

Singlet oxygen (1O2) is the major cytotoxic agent during type-II photodynamic therapy (PDT). The production of 1O2involves the complex reactions among cancer agent, oxygen molecule, and treatment laser light. The light propagation in tumor tissue is described by the diffusion equation. In this work, an optimization routine is developed to fit the [1O2]rx profile to the simulated necrosis ...

Finite Element Analysis of Molecular Rydberg States

M.G. Levy[1], X. Liang[1], R.M. Stratt[1], and P.M. Weber[1]

[1]Department of Chemistry, Brown University, Providence, Rhode Island, USA

Identifying molecules requires associating molecular structures with their electronic energy levels. In this paper we introduce a novel technique for the calculation of molecular Rydberg levels. The technique allows for easy visualization of the associated wavefuntions to make unambiguous assignments. The value calculated for the 3p state of trimethylamine is most closely in agreement with recent ...

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 validate ...

Accelerating R&D with COMSOL: A Personal Account

Erik Birgersson[1]

[1]Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore

This presentation gives an account of how COMSOL Multiphysics® software has helped to accelerate research and development. It has been used to simulate energy systems such as fuel cells, biomedical systems such as hydrogels and human skin, and monolithic catalytic converters. Each of these systems requires a mathematical model that can accurately represent the relevant physics, and which can be ...

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 ...

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 ...

Calculation of the Magnetic Field Intensity in a Rectangular Conductor Carrying Current in Electromagnetism Introductory Courses

J.C. Olivares-Galvan[1], I. Hernandez[2] , P.S. Georgilakis[3], and L.E. Campero[1]

[1]Universidad Autónoma Metropolitana, Azcapotzalco, Mexico, D.F.
[2]Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Guadalajara, Guadalajara, Jalisco, Mexico
[3]School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece

This paper describes a type of didactic material used when teaching electromagnetism. The purpose is to guide the students to verify the results of a Finite Element (FE) simulation using those obtained analytically. This procedure has shown to be of great help during their learning of the FE method. The example in this paper uses a 2D analytical method to estimate the magnetic field generated by ...

Making Cartograms and Using them for Data Acquisition

P. Mercure[1], and R. Haley[2]
[1]The Dow Chemical Company, Midland, MI
[2]ATM Research, Midland, MI

We demonstrate cartogram construction, where a geographical map is distorted to represent some measure, for example population, while trying to keep the shape of regions recognizable. We then apply this cartogram construction technique to optimize thermocouple locations. A heat generation and conduction model is used initialize the cartogram construction algorithm. A uniform distribution of ...

Development of the Service Frame for SBS Tracker GEM and TENDIGEM Development

F. Noto[1], E. Cisbani[2], F. Librizzi[1], F. Mammoliti[3], C.M. Sutera[1]
[1]Istituto Nazionale Fisica Nucleare - Sezione di Catania, Catania, Italy; Dipartimento di Fisica ed Astronomia, Università di Catania, Catania, Italy
[2]Istituto Nazionale Fisica Nucleare - Sezione di Roma, Roma, Italy; Istituto Superiore di Sanità, Roma, Italy
[3]Istituto Nazionale Fisica Nucleare - Sezione di Catania, Catania, Italy; Dipartimento di Fisica ed Astronomia, Università di Catania, Catania, Italy

The Gas Electron Multiplier (GEM) technology has been proven to tolerate rate larger than 50 MHz/cm² without noticeable aging and to provide the sub-millimeter resolution on working chambers up to 45x45 cm² [1]. A new GEM tracker is under development for the upgrade of the SBS spectrometer in Hall A at Jefferson Lab. The chambers of the tracker have been designed in a modular way: each chamber ...

Multi-Objective Optimization of a Ball Grid Array Using modeFRONTIER® and COMSOL Multiphysics®

H. Strandberg[1], T. Makkonen[2], and J. Leinvuo[2]
[1]ESTECO Nordic AB, Lund, Sweden
[2]VTI Technologies Oy, Vantaa, Finland

Capacitive MEMS (Micro-Electro-Mechanical Systems) accelerometers may be directly soldered to the printed circuit board by an array of solder balls. Differences in the thermal expansion coefficients of the pertinent materials cause deformations of the accelerometer under temperature change. This may cause a relative movement of the sensing masses with respect to the sensing electrodes, resulting ...

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