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.

Simulation of Vector Mode Grating Coupler Interfaces for Integrated Optics

C. T. Nadovich [1],
[1] Lafayette College, Easton, PA, USA

The use of grating couplers to couple conventionally phased and polarized light near vertically in and out of optical slab or film waveguides [1] represents an attractive method to interface optical fiber to photonic ICs. Previously developed grating coupler designs use transversely uniform grating structures matched to conventional scalar fiber modes. The performance of these geometries can be ...

Modeling Electrical and Thermal Conductivities of Biological Tissue in Radiofrequency Ablation

M. Trujillo[1], E. Berjano[1]
[1]Universidad Politécnica de Valencia, Valencia, Spain

Radiofrequency ablation is a minimally invasive techinique which is used to treat some kinds of cancer. The realism of theoretical models is very important. An influential factor in this realism is mathematical functions that model the temperature-dependence of tissue thermal and electrical conductivities. The aim of this work is to review the mathematical functions employed to model the ...

3D Modeling of Planar Discharge of a CO2 Laser

J. Schüttler [1],
[1] Rofin-Sinar Laser GmbH, Hamburg, Germany

High power CO2 lasers have been the workhorses for sheet metal cutting, welding and many more applications in materials processing during the past decades. Even though a significant replacement by fiber coupled lasers takes place, there are still many applications that benefit from the characteristics of CO2 lasers with a high beam quality. Modeling the plasma behavior is essential for ...

Optical and Electrical Modeling of Three Dimensional Dye Sensitized Solar Cells

P. Guo[1]
[1]Northwestern University, Evanston, IL, USA

Dye sensitized solar cells (DSSCs) have received tremendous attention as alternative photon harvesting devices. While the sintered TiO2 nanoparticle network attached with dye molecules achieves efficient photon absorption, the electrons have to diffuse through the long TiO2 network to reach the contact, resulting in a high electron density and thus increased recombination. Extensive research ...

Prediction and Optimization of Surface-Enhanced Raman Scattering Geometries using COMSOL Multiphysics

I. Knorr, K. Christou, J. Meinertz, A. Selle, J. Ihlemann, and G. Marowsky
Laser-Laboratorium Göttingen e.V., Germany

Raman spectroscopy is a commonly used tool in biodiagnostics and sensor technology. Surface-enhanced Raman scattering provides high signal enhancements especially at nanostructured metallic surfaces. In this paper the electromagnetic Raman enhancement from different metallic nanostructures - including gold coated gratings, spherical and hemispherical particles - is calculated by using the finite ...

Key-Holes Magnetron Design and Multiphysics Simulation

A. Leggieri[1], F. Di Paolo[1], D. Passi[1]
[1]Univeristy of Rome "Tor Vergata" - Department of Electronic Engineering, Rome, Italy

This paper describes the design and characterization of an 8 slots resonant cavity Magnetron, which undergoes thermal-structural effects due to cathode heating. The proposed study involves Thermal Stress, Eigen-frequency and Particle Tracing analysis based on COMSOL Multiphysics®. Magnetrons are well known and often utilized High Power Radiofrequency Vacuum Tube oscillators. In order to ...

Simulations of Negative Curvature Hollow-core Fiber - new

J. Zhang[1], Z. Wang[1], J. Chen[1]
[1]College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha, Hunan, China

COMSOL Multiphysics® software was used to simulate and analyze the transmission attenuation spectra of the negative curvature hollow-core fiber (NCHCF) over the wavelength from 2.7 μm to 4.2 μm. The effect of thickness of capillaries and the effect of the distance between the capillaries on confinement loss spectra were studied, which agreed well with the high-loss and low-loss bands predicted ...

A Design-of-Experiments Approach to FEM Uncertainty Analysis for Optimizing Magnetic Resonance Imaging RF Coil Design - new

J. T. Fong[1], N. A. Heckert[1], J. J. Filliben[1], L. Ma[1], K. F. Stupic[2], K. E. Keenan[2], S. E. Russek[2]
[1]National Institute of Standards & Technology, Gaithersburg, MD, USA
[2]National Institute of Standards & Technology, Boulder, CO, USA

The design of a magnetic resonance imaging (MRI) RF coil using finite element method-based analysis is an essential part of a multi-year research project at the National Institute of Standards and Technology, Gaithersburg, Maryland, where the goal of the project is to develop a “phantom” for calibrating MRI machines that is traceable to standardized values. Traceable MRI calibrations are ...

Uncertainty of FEM Solutions Using a Nonlinear Least Squares and Design of Experiments Approach

J. T. Fong [1], N. A. Heckert [1], J. J. Filliben [1], P. V. Marcal [2], R. Rainsberger [3]
[1] National Institute of Standards and Technology, Gaithersburg, MD, USA
[2] MPACT Corp., Oak Park, CA, USA
[3] XYZ Scientific Applications, Inc., Livermore, CA, USA

Uncertainty in COMSOL Multiphysics® software simulations due to (a) model parameter uncertainties and (b) mesh-induced truncation errors, is estimated using a design-of-experiments approach [1, 2, 3], and a nonlinear least squares logistics fit method [4, 5], respectively. Examples to illustrate both approaches are given using the COMSOL RF Module (in an application of a MRI coil design) and ...

Modeling Microwave Heating During Batch Processing of a Liquid Sample in a Single Mode Cavity

S. Curet [1], F. Bellicanta Begnini [1], O. Rouaud [1], L. Boillereaux [1]
[1] L’UNAM Université, ONIRIS, CNRS, GEPEA, Nantes, France

The use of microwaves for heating purposes of dielectric materials is encountered in many industrial applications (food processing, chemistry, material engineering and medical applications). In most of these thermal applications, the prediction of the temperature evolution within the processed materials is of primary interest in order to optimize the treatment (Chandrasekaran et al., 2013). In ...