Aqui você encontrará apresentações realizadas nas Conferências de Usuários COMSOL de todo o mundo. As apresentações englobam pesquisas e produtos inovadores feitas por engenheiros e cientistas usando o COMSOL Multiphysics. Os tópicos abrangem uma grande gama de indústrias e aplicações, como elétrica, mecânica, escoamento e química. Use a função de busca "Quick Search" para encontrar apresentações na sua área de interesse.

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 ...

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 ...

Field-Circuit Coupling Applied to Inductive Fault Current Limiters

D. Lahaye[1], D. Cvoric[2], S. de Haan[2], and J. Ferreira[2]
[1]Delft Institute of Applied Mathematics, Department of Electrical Engineering, Mathematics and Computer Sciences, TU Delft, The Netherlands
[2]Electrical Power Processing Unit Department of Electrical Engineering, Mathematics and Computer Sciences, TU Delft, The Netherlands

Fault Current Limiters (FCLs) are expected to play an important role in the protection of future power systems due to the rising levels of the short-circuit currents. The inductive FCLs, comprising magnetic cores and one or more dc and ac windings, are particularly interesting because they inherently react on the fault. The so-called open-core FCL configuration employs only one magnetic core for ...

Passive Microsensor Based on LC Resonators for Substance Identification

D.A. Sanz Becerra[1], E.A. Unigarro Calpa[1], J. Osma[1], F. Segura[1]
[1]Universidad de los Andes, Bogotá, Colombia

A scheme for inductive wireless powering and readout of passive LC sensor is presented. The sensor’s inductor is designed as a planar square coil and is used as the power receiving component. The capacitor is connected directly to the inductor and it was designed as an interdigital capacitor. With a transmitting coil (coupling antenna), an electromagnetic field is generated which couples with ...

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 ...

Modeling of Piezoelectric Transducers Made of PZT for Energy Harvesting

J. Golebiowski [1], P. Bakolik [2],
[1] Lodz University of Technology, Department of Semiconductor and Optoelectronics Devices, Poland
[2] Lodz Univeristy of Technology, Poland

This work shows the results of modeling of piezoelectric transducers used to recover energy from mechanical vibrations. The analysis consists of usefulness of commercial ceramic PZT transducers to power electronic systems. Determined output load characteristics, characteristics of the effect of stress on the output power. Systems, which recover electrical energy for example from mechanical ...

微波干燥电磁场、多相传输及大变形三维耦合模型

张春 [1], 朱铧丞 [1], Ashim Datta [1],
[1] 四川大学,成都,四川,中国

引言:微波干燥过程涉及多物理场的耦合,物理过程十分复杂。不仅有被加热物质的形态改变,还有气态、液态和固态三相的相互作用。为了更清楚地理解微波干燥过程,本模型将电磁场、多相流和物理变形用相应的方程耦合到一起建模分析,并用相应的物理参数表征微波干燥过程。(图1) COMSOL Multiphysics® 的使用:借鉴微波加热接口土豆模型,添加气体和固体传热接口以及自定义方程,用方程和参数实现多物理场耦合。实验模型中,干燥物为土豆,且被视为多孔弹性介质。物质变形用相应的矩阵来表征。 结果:在仿真结果的基础上,利用家用微波炉干燥土豆,设计实验,并测量了微波干燥过程中的重要物理参数,如温度、水分和形变。(图2,图3) 结论:该仿真模型和实验基本吻合,较清晰地反应了微波干燥的复杂物理过程。

COMSOL Multiphysics Modeling for Design Optimization of Eddy Current Crack Detectors

E. Weststrate, M. Steinback, N. Rensing, and T. Tiernan
Radiation Monitoring Devices Inc., Watertown, MA, USA

Passing alternating current through a wire placed just above a conducting surface induces eddy currents in that surface. Any cracks present in the conductor modify the eddy current distribution, creating a magnetic field signature unique to the crack. This magnetic signature can be detected by placing magnetic field sensors such as magnetoresistive sensors or inductive loop pickups in close ...

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 ...

COMSOL Multiphysics® Software: Time-Lapse Electrical Resistivity Inversion - new

T. K. Chou[1], M. Chouteau[1], M. J. Yi[2]
[1]Department of Civil, Geological & Mining Engineering, École Polytechnique de Montréal, Montreal, QC, Canada
[2]Korea Institute of Geoscience and Mineral Resources, Daejeon, South Korea

Time-lapse electrical resistivity tomography (ERT) method provides a non-invasive way to monitor subtle sub-surface changes caused by water flow such as in an infiltration test. Problems arise when the inversion models contain artifacts due to measurement errors, rapid change in soil electrical property during measurement time, etc. A new approach was developed by Kim et al. (2004) and (2009) ...