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.

Simulation and Verification of a Capacitive Proximity Sensor

T. Schlegl, and H. Zangl
Graz University of Technology
Graz, Austria

State of the art proximity sensors are most often based on optical or tactile methods. Although these sensor systems are widely used (e.g. clamping protection) the reveal several drawbacks. Most optical sensors need a line of side whereas tactile sensors cannot be used to determine a distance to an approaching object. Capacitive sensing technology has proven to be an interesting alternative to ...

Design of Dielectrophoretic Cell Traps in Microfluidics Devices Using COMSOL Multiphysics® Software

L. Velmanickam [1], K. Nawarathna [1],
[1] Department of Electrical and Computer Engineering, North Dakota State University, Fargo, ND, USA

The isolation of target cells from biological samples such as serum, urine or blood in high-throughput manner without contamination with other cells is the starting point of developing effective therapy for many diseases. Currently available methods for cell isolation/separation require extra labeling. Furthermore, separating target cells using current methods do not produce pure target cell ...

Secondary Electron Trajectories in Scanning Tunneling Microscopy

H. Cabrera [1], D. A. Zanin [1], L. G. De Pietro [1], A. Vindigni [1], U. Ramsperger [1], D. Pescia [1],
[1] Laboratory for Solid State Physics, Microstructure Research, ETH Zurich, Zurich, Switzerland

The recently developed technique Scanning Tunneling Microscopy in the Field Emission regime (STM FE) is based on the Russell Young's topografiner technology. The set-up is a no contacting device consisting of a sharp tip approached vertically to a conducting surface at variable distances and biased with a small voltage with respect to the surface. The system builds a junction across which ...

Modelling of a Differential Sensor in Eddy Current Non-destructive Evaluation

A. Rosell[1], and G. Persson[2]
[1]Volvo Aero Corporation, Trollhättan, Sweden
[2]Chalmers University of Technology, Göteborg, Sweden

Interaction between the probe and a defect in eddy current non-destructive evaluation is studied. Evaluation of sensor signal response is the basis for the calculation. In this work a differential sensor is considered and the problem regarded here is problem 8 from the testing of electromagnetic analysis methods (TEAM) workshops. The truncation, referring to the position of the outer ...

On the Simulation of the Lightning Strikes to Complex Grounded Structures

M. Becerra
Royal Institute of Technology
School of Engineering
Electromagnetic Engineering Lab
Stockholm, Sweden

There is a considerable world-wide interest among lightning protection engineers and designers on the improvement of the standard procedures to assess the location of the most vulnerable places on complex structures to be struck by lightning flashes. This paper presents the implementation of the Self-consistent Lightning Interception Model in Matlab by using the COMSOL Multiphysics 3.5 ...

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 ...

Analysis of a Prototype MRI Hybrid Birdcage RF Coil with Uncertainty Quantification (*)

J. T. Fong [1],
[1] National Institute of Standards & Technology, Gaithersbug, MD, USA

1. INTRODUCTION. In a magnetic resonance imaging (MRI) system (see Fig. 1), it is necessary to excite the nuclei of a patient into coherent precession for imaging. This requires coupling between the nuclei and a source of radio frequency (RF) power (the transmitter). To receive a meaningful signal, one also needs to couple the nuclei to an external circuitry (the receiver). These two ...

Looking for the Origin of Power Laws in Electric Field Assisted Tunneling

H. Cabrera[1], D.A. Zanin[1], L.G. De Pietro[1], A. Vindigni[1], U. Ramsperger[1], D. Pescia[1]
[1]Laboratory for Solid State Physics, ETH Zurich, Zurich, Switzerland

A sharp tip approached perpendicular to a conducting surface at subnanometer distances and biased with a small voltage builds a junction across which electrons can be transferred from the tip apex to the nearest surface atom by direct quantum mechanical tunneling. Such a junction is used e.g. in Scanning Tunneling Microscopy (STM). When the distance d between tip and collector is increased ...

Numerical Simulation of Electrokinetic Convection-Enhanced Delivery of Macromolecules

Y. Ou [1], A. Jaquins-Gerstl [1], S. G. Weber [1],
[1] Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA

The brain is a heterogeneous porous medium with regions of anisotropy. Measurements of tortuosity (λ) showed that diffusion in gray matter (e.g. striatum) is isotropic (λ = 1.65), whereas it is anisotropic in white matter (e.g. corpus callosum) (λparallel = 1.38, λperpendicular = 1.80)[1-2]. Pressure-driven convection-enhanced delivery (CED) of macromolecules (e.g. drugs) was first described in ...

Highest Pulsed Magnetic Fields in Science and Technology, Assisted by Advanced Finite-Element Simulation

Thomas Herrmannsdörfer

Dr.
Forschungszentrum Dresden-Rossendorf, Germany

Thomas Herrmannsdörfer got his PhD in experimental physics from the University of Bayreuth in 1994. In 1995, he received the Research Award of the Emil-Warburg-Foundation while he worked at the DFG-Graduiertenkolleg Bayreuth. From 1995 – 1998 he worked as a scientist at Hahn-Meitner-Institute (HMI) Berlin. Since 1998, he has worked at Forschungszentrum Dresden ...