Sonsight Inc. / NSWC, Accokeek, MD, USA
Cogging torque in permanent magnet motors and generators is characterized by a torque ripple. These torque fluctuations cause vibrations, noise and speed fluctuations. This paper presents finite element (FE) analyses results that show a previously unaddressed low frequency modulation of cogging torque ripple. The paper resulted in an analytical formulation of cogging torque with low frequency ...
张春 , 朱铧丞 , Ashim Datta ,
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。
Z. Wu , H. Kemper ,
 Energy Storage Systems, FH Aachen, Aachen, Germany
Vehicles with battery as energy storage fascinate more and more people. Meanwhile, more questions are surfaced – How to ensure a safe operation of the battery package? How long could the cycle life of a battery package reach? Can a battery package be operated in any environmental circumstance? All these questions are the driving forces of our work – development of the optimal battery packs for ...
P. Masson, and R. Meinke
Advanced Magnet Lab, Palm Bay, Florida, USA
Superconductors have the unique capability of trapping magnetic flux. This feature has the potential to enable and improve several applications including high power density rotating machines. Current material used as trapped flux magnets (TFM) is single domain YBCO that present numerous limitations interms of performance, stability and size. One way to overcome the limitations is to use thin ...
A.Weddemann, D. Kappe, and A. Hütten
Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge MA, USA
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 ...
B. Hannon, P. Sergeant
Ghent University, Ghent, Belgium
In the field of electric machines, a trend towards both higher efficiency and higher power density is observed. This has led to a growing importance of Permanent Magnet Synchronous Machines. However, the magnets used in these machines risk demagnetization at high temperatures. Especially in machines operated at high speeds. A commonly proposed solution is the shielding cylinder (SC), a ...
V. Riccardi ,
 Cesare Bonetti, Garbagnate Milanese, Italy
The aim of the simulation is to study the behavior of a particular arrangement of a sealing system made of a Toroidal Spring Coil encapsulated in an thin casing, which is provided with a circumpherential cut to permit the pressure fill it inside. The mechanical simulation implemented in COMSOL Multiphysics® software is necessary to understand the displacements and stresses of the structure ...
Sensibility Analysis of Inductance Involving an E-core Magnetic Circuit for Non Homogeneous Material
K. Z. Gomes , T. A. G. Tolosa , E. V. S. Pouzada ,
 Mauá Institute of Technology, São Caetano do Sul, SP, Brazil
In this work, a methodology is developed, based on the application of finite element method in the frequency domain, using the COMSOL Multiphyics software, aiming the sensibility analysis of inductance calculation involving some configurations of an E-core magnetic circuit. Such important analysis, are made from several geometries and considering different frequencies for the source current ...
J. T. Fong ,
 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 ...
R. Brambilla and F. Grilli
ENEA - Ricerca sul Sistema Elettrico S.p.A., Milano, Italy
Karlsruhe Institute of Technology, Karlsruhe, Germany
In this paper we present a summary of our work on numerical modeling of superconductors with COMSOL Multiphysics®. We discuss the two models we utilized for this purpose: a 2-D model based on solving Maxwell equations and a 1-D model for thin conductors based on solving the integral equation for the current density distribution. The latter is useful for modeling second generation High ...