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.
COMSOL News Magazine 2017

Doping Dependent I-V Characteristics of Single Silicon Nanowire

S. Mishra [1], S. K. Saxena [1], P. Yogi [1], P. R Sagdeo [1], R. Kumar [1],
[1] Indian Institute of Technology Indore, Indore, Madhya Pradesh, India

In the present work, we have studied the electron transport properties of single silicon nanowire using Semiconductor Module of COMSOLMultiphysics software. We construct a MSM (metal-semiconductor-metal) model where metal is selected as copper and semiconductor is taken as silicon. Silicon is doped with n-type impurity by increasing doping concentration. Further, the Schottky diodes formed at ...

Simulation of Flaw Signals in a Magnetic Flux Leakage Inspection Procedure

O. Nemitz, and T. Schmitte
Salzgitter Mannesmann Forschung GmbH, Duisburg, Germany

In the inspection of steel products with respect to flaws a magnetic flux leakage (MFL) test procedure can be applied. In this procedure a “horseshoe” shaped yoke is used, whose legs are wrapped with coils through which an alternate current with a high frequency (3 kHz) is flowing. Hereby a thin magnetic field is induced near the surface of the test object which leaks from the material if a flaw ...

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 ...

Finite Element Modeling of Remote Field Eddy Current Phenomenon

T. Jayakumar[1], B. Purnachandra Rao[2], C. K. Mukhopadhyay[3], B. Sasi[2], V. Arjun[5], S. Thirunavukkarasu[2]
[1]Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, TN, India
[2]Nondestructive Evaluation Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, TN, India
[3]EMSI Section, Nondestructive Evaluation Division, Indira Gandhi Centre for Atomic Research, Kalpakkam, TN, India
[5]NDE Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, TN, India

Remote field eddy current (RFEC) technique is a method of detecting defects in ferromagnetic tubes. This is based on low frequency eddy current, which employs an exciter coil and a receiver coil separated by a characteristic distance. The exciter is fed with a low frequency sinusoidal current and the receiver coil senses the perturbation of the magnetic fields caused by the eddy currents in the ...

Numerical Analysis of the Response of Thick Wires to Extreme Dynamic Electro-Mechanical Loads - new

R. Cunrath[1], M. Wickert[2]
[1]Fraunhofer EMI, Efringen-Kirchen, Germany
[2]Fraunhofer EMI, Freiburg im Breisgau, Germany

Research at Fraunhofer EMI addresses the response of materials in extreme dynamic loads. Besides mechanical or thermal loads, intense electric pulse currents also represent an extreme dynamic load. Experimentally, metallic samples, mainly thick wires, were electro-mechanically loaded with currents up to 400 kA. For this purpose, a test rig containing a high-voltage pulsed power supply and high ...

Magnetic Devices For a Beam Energy Recovery THz Free Electron Laser - new

R. R. S. Caetano[1], G. Cernicchiaro[2], R. M. O. Galvão[3]
[1]Universidade Federal do Rio de Janeiro, Macaé, RJ, Brazil
[2]Centro Brasileiro de Pesquisas Físicas, Rio de Janeiro, RJ, Brazil
[3]Instituto de Física USP, São Paulo, SP, Brazil

This paper presents a numerical analysis of magnetic devices, dipole, quadrupole and undulator and a THz Free Electron Laser (FEL) electron-beam recovery system. Free Electron Laser are an important source of coherent radiation being used in the study of chemical properties of substances, thus being an important tool for various fields of science such as condensed matter physics, chemistry, ...

Modeling Directional Two Arm Archimedes Spiral Coils in the RF Electromagnet Range

A. Kalinowski, and J. Maguire
Naval Undersea Warfare Center/Div. Npt. , Newport, RI, USA

The paper addresses a class of problems for modeling and consequently simulating the electromagnetic field radiation pattern from a two arm Archimedes spiral coil. The performance of particular interest is knowledge of the radiated magnetic field H and electric field E in the neighborhood of the coil. The results in this paper illustrate how COMSOL is used to solve for the radiated ...

A Modeling Study of Electrical Characteristics of Anisotropic Conductive Film Adhesives

R. Divigalpitiya
3M Canada Company, London, ON, Canada

Finite element analysis provides new insights into the electrical behavior of conducting adhesives. We show that at a contact between a spherical conducting particle and a flat conducting substrate the current distribution is non-uniform: the current is concentrated at the periphery of the contact. In practice, the current concentration has important implications. We further shed light on what ...

The Effect of Space Charge due to the Auto-Ionization of Neutral, Hydrogenic States in Point-Contact Germanium Detectors at MilliKelvin Temperatures - new

D. Faiez[1], N. Mirabolfathi[1], B. Sadoulet[1], K. M. Sundqvist[2]
[1]Department of Physics, University of California - Berkeley, Berkeley, CA, USA
[2]Department of Electrical & Computer Engineering, Texas A&M University, College Station, TX, USA

A class of semiconducting detectors, operated at temperature T~50mK, has direct application to the search for dark matter particle, when are able to simultaneously measure both the ionization and phonons created by particle interactions. We explore the effect of space charge accumulation in a germanium p-type point contact detector which arises due to the auto-ionization of hydrogenic ...

AC Electrothermal Characterization of Doped-Si Heated Microcantilevers Using Frequency-Domain Finite Element Analysis - new

K. Park[1], S. Hamian[1], A. M. Gauffreau[2], T. Walsh[2]
[1]Mechanical Engineering Department, University of Utah, Salt Lake City, UT, USA
[2]Department of Mechanical, Industrial & Systems Engineering, University of Rhode Island, Kingston, RI, USA

This work investigates the frequency-dependent electrothermal behaviors of freestanding doped-silicon heated microcantilever probes operating under the periodic (ac) Joule heating. The transient heat conduction equation for each component (i.e., the low-doped heater region, the high-doped constriction region, and the high-doped leg region) is solved using the general heat transfer module for DC ...