李晓南 , 刘国强 ,
利用惯性力学和电磁学，研究了一个金属小车沿着磁铁铺就的轨道做减速直线运动。其中，小车也可以看成是携带等量的磁铁剩磁，且沿着铁磁轨道减速运动。通过赋予小车一个初速度，例如100 m/s，然后再根据实际情况、赋予它一个特征密度，即小车有了一定的质量。当认为小车沿水平方向的轨道减速运动，忽略重力、空气阻力等其他一些影响因素时，小车将只受电磁的洛伦兹力的作用，而逐渐减速到零。 利用最新版的 COMSOL Multiphysics®，建模过程中，主要用到了“磁场和电场(mef)”和“全局常微分和微分代数方程(ge)”接口，涉及到的动力学和电磁学方程为 dv/dt=F/m F ⃗=∫_(V_vehicle)▒〖(J_induced ) ⃗×B ⃗dv〗 J_(i_y)=σ(v_z∙B_x-v_x∙B_z ) v 为小车即时速度，F 为洛伦兹力，J 为感应产生的涡流，v 为速度，B ...
P. J. Masson, and R. B. Meinke
Advanced Magnet Lab, Palm Bay, Florida, USA
Charged particle beam manipulation requires magnetic dipoles for steering and quadrupoles for focusing. Conventional magnets are currently used leading to very large and heavy systems. Miniaturization of the optic magnets would enable the development of more affordable systems and potentially portable devices. The Advanced Magnet Lab, Inc. has developed a revolutionary magnet topology and ...
D. Lahaye, D. Cvoric, S. de Haan, and J. Ferreira
Delft Institute of Applied Mathematics, Department of Electrical Engineering, Mathematics and Computer Sciences, TU Delft, The Netherlands
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 ...
S. Barth, and S. Zimmermann
Drägerwerk AG & Co. KGaA, Lübeck, Germany
Ion mobility spectrometry provides fast detection of very low concentrations of chemical substances. Simple instrumentation combined with high sensitivity and high selectivity are the advantages of this technique. One well established field of application is the detection of hazardous compounds in air, such as chemical warfare agents, explosives and pollutants. A numerical model based on finite ...
Modeling Of A Single Pulse Electric Discharge At Sphere/Flat Interface By Coupling Contact Multiphysics And Phase Transformations
G. Maizza, P. Di Napoli, and R. Cagliero
Dipartimento di Scienza dei Materiali ed Ingegneria Chimica, Politecnico di Torino, Torino, Italy
Contact electro-thermal phenomena are of great theoretical and technological interest to a large number of processing applications, such as spot welding, current-assisted sintering, electrical circuitry (switches) and motors. A model has been developed, aiming at predicting physical and metallurgical phenomena in a steel sample upon rapid heating induced by current pulse discharge. Electric ...
E. Scotoni, C. Tozzo, D. Zoccarato, F. Paganini
TMC Italia, Busto Arsizio, Italy
COMSOL, Brescia, Italy
A three phase transformer with very low harmonic pollution transferred back to power line is here presented. In fact, thanks to the described setup, intermediate harmonics (5th and 7th) are not going out back to the power line feeding the primary. These results has been extensively validated versus measurements performed on produced and shipped machine. With these results, TMC is then featuring ...
A.N. Shiraz, A. Demosthenous
E&EE Department, University College London, London, United Kingdom
After spinal cord injury (SCI) the functions of the lower urinary tract are often disrupted and may have fatal consequences for the patient. It has been shown that using a transrectal probe developed by Craggs et al., through conditional transrectal stimulation of pudendal nerve, it is possible to treat hyperreflexia in some of the SCI patients. To maximise the efficacy of this type of ...
Effect of a High Frequency Field on the Electric Double Layer Surrounding a Biomolecule in a Fluid - new
M. Riou, C. Maedler, S. Erramilli, P. Mohanty
Boston University, Boston, MA, USA
Biosensors based on silicon nanowires are of great interest for ultrasensitive biomolecular recognition of disease specific markers for early stage diagnosis . However, there are limitations on the performance of these nanosensors in solutions at high ionic strength. This is because the electric field induced by the binding of biomolecule is partially screened on length-scales larger than the ...
3D Electro-Thermal Study for Reliability of Automotive Power Vertical MOSFET Using COMSOL Multiphysics®
T. Azoui, S. Verde, J.B. Sauveplane, and P. Tounsi
LAAS-CNRS, Toulouse, France
Department of Electronics and Telecommunications Engineering, University of Naples Federico II, Naples, Italy
In this paper 3D electro-thermal FE Model using COMSOL Multiphysics® software of power vertical MOSFET used in the automotive industry is presented. This model is used to analyze the effects of bonding wire lift off defect and to study the influence of metallization thickness and number of bonding wires on the electrical and thermal behavior of the power device. The maximum temperature ...
B. LaBarge, and E. Gutierrez-Miravete
Gems Sensors and Controls, Plainville, CT, USA
Rensselaer at Hartford, Hartford, CT, USA
A simple proximity sensing circuit is made using magnets actuating reed switches; these switches are wired into a larger circuit that performs auxiliary functions. The success or failure of such systems is a function of their position. A simulation using COMSOL Multiphysics is conducted to study the position of a reed switch relative to a magnet when the switch opens and closes. Ability to ...