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.

Analysis and Design of Antennas for an Implantable Medical Device System for Functional Electrical Stimulation

H. Suri[1]
[1]Alfred Mann Foundation for Scientific Research, Valencia, CA, USA

This poster outlines the results of finite element analyses to study the antenna radiation pattern of an implanted medical device. Also presented are simulation results used to design an electrically small antenna for a portable control unit that communicates with the implants over the Medical Micropower Network Frequency Range [413 MHz to 457 MHz]. Alfred Mann Foundation’s Functional Electrical ...

Superconducting RF Cavity Performance Degradation after Quenching in Static Magnetic Field

I. Terechkine[1], T. Khabiboulline[1], D. Sergatskov[1]
[1]Fermi National Accelerator Laboratory, Batavia, IL, USA

Performance degradation of a superconducting RF cavity after quenching in an external magnetic field was calculated using COMSOL. This degradation is due to the increased resistance of a superconducting surface with trapped magnetic flux. The amount of the trapped flux depends on the size of the normally-conducting opening that develops in the superconducting wall of a cavity during quenching. ...

Design Optimization of Waveguide Applicator for Microwave Hyperthermia Cancer Treatment

P. Kumar [1], S. Kalra[1], A. Marwaha[1]
[1]Department of Electronics and Communication Engineering, Sant Longowal Institute of Engineering Technology Longowal, Punjab, India

The optimized design of a waveguide applicator has been proposed for superficial microwave hyperthermia using COMSOL Multiphysics 3.5a. In microwave hyperthermia cancer treatment body tissue is exposed to high temperatures using external and internal heating devices. Non-Invasive or external hyperthermia is used to treat tumors that are in or just below the skin (superficial). Non-invasive ...

Numerical Optimization Technique for the Optimal Design of the Surface Plasmon Grating Coupler

C. Caiseda[1], V. Aksyuk[2], I. Griva[3]
[1]Inter American University of Puerto Rico, Bayamon, PR, USA
[2]National Institute of Standards and Technology, Gaithersburg, MD, USA
[3]George Mason University, Fairfax, VA, USA

The optimal design of the grating coupler for surface plasmon generation is revisited for its interdisciplinary importance in the efficient use of energy, and the strong dependence of the energy convergence rate of the system on the design. This work contributes a comprehensive gradient based numerical optimization technique to optimize both geometry of the grating and parameters of the ...

Optimized Illumination Directions of Single-Photon Detectors Integrated with Different Plasmonic Structures

M. Csete[1], Á. Sipos[1], A. Szalai[1], G. Szabó[1]
[1]Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary

The optimal orientations of different single-photon detector designs were determined by COMSOL software package. Absorption of niobium-nitride (NbN) stripes in two different (p=220 nm, 3p=660 nm) periodic patterns integrated with plasmonic elements was studied. In OC-SNSPDs consisting of ~quarter-photon-wavelength nano-cavity the optimum direction is perpendicular incidence onto NbN stripes in P ...

Multiphysics Analysis of Normal Conducting RF Cavities for High Intensity Proton Accelerators

M. Hassan[1], I. Gonin[1], T. Khabiboulline[1], V. Yakovlev[1]
[1]Fermi National Accelerator Laboratory, Batavia, IL, USA

Normal conducting cavities are typically used in the front end of proton accelerators to get the beam accelerated to velocities approximately a few tenths of the speed of light, where superconducting cavities can then be used to accelerate the beam to the speed of light. The warm part of a typical proton accelerator would contain a radio frequency quadrupole (RFQ) and several buncher cavities. ...

Optimization of 3D Layered Metal-Dielectric Stacks (MDS) for Near-Field Fluorescence Imaging

P.S. Tan[1], K. Elsayad[2], K. Heinze[1]
[1]Rudolf Virchow Center, University of Würzburg, Würzburg, Germany
[2]Research Institute of Molecular Pathology (IMP), Vienna, Austria

Nano-structures consisting of layered metal-dielectric stacks (MDSs) can be designed to have evanescent transmission and reflection coefficients that oscillate as a function of transverse wavevector and frequency. However, these structures always suffer from the material losses and surface roughness that are detrimental to image reconstruction. As such, we propose an optimized planar anisotropic ...

An Assessment of the Suitability of the Body and Adult Head Coils for Transmission during Paediatric Magnetic Resonance Imaging

G.R. Cook[1], M.J. Graves[1], F.J. Robb[2], D.J. Lomas[1]
[1]Department of Radiology, University of Cambridge, Cambridge, United Kingdom
[2]General Electric Healthcare Coils, Aurora, Ohio, USA

MRI offers many advantages over other modalities and its lack of ionizing radiation is important for children, but can be limited by the radio-frequency (RF) coils available. This work calculates Specific Absorption Rate (SAR) and homogeneity of the RF transmit field (B1+) when imaging infants in adult coils. Two birdcage-type coils were loaded by a tissue model and their B1+ homogeneities ...

Multi-Layers Surface Coil Design: Geometry Optimization - new

S. Aissani[1], L. Guendouz[2]
[1]CRM2, Institut Jean Barriol, University of Lorraine, Vandoeuvre-lès-Nancy, France
[2]Mesures et architectures électroniques, University of Lorraine, Vandoeuvre-lès-Nancy, France

Nuclear Quadrupole Resonance (RQN) is a radio frequency (RF) spectroscopic technique that is used to detect quadrupole nuclei such as Nitrogen-14. NQR was found to be a good candidate for detecting narcotics, explosives and medicines [1]. However, due to its low sensitivity the use of NQR is still limited. One way to increase the sensitivity is to improve the RF coil by means of a better RF ...

Scattering of mm-Waves by Turbulent Structures in Magnetically Confined Fusion Plasmas

O. Chellaï [1], S. Alberti [1], I. Furno [1], T. Goodman [1], M. Baquero [1]
[1] Centre de Recherches en Physique des Plasmas, Ecole Polytechnique Fédérale de Lausanne, Suisse

In magnetically confined fusion devices, electron cyclotron resonance heating (80-170 GHz) is characterized by a local RF-power deposition at the electron cyclotron resonance [1]. A mm-wave RF Gaussian beam is launched from a dedicated antenna and propagates through the highly turbulent scrape-off layer (SOL) at the edge of the confined plasma. Turbulence in the SOL is characterized by ...