1,263 results on '"electromagnetic force"'
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202. 四轨电磁发射器不同构型枢轨静力学分析.
- Author
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李腾达, 冯 刚, 刘少伟, 任师达, and 范成礼
- Abstract
Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2021
- Full Text
- View/download PDF
203. A Study on Asymmetry of Electromagnetic Force Modes of Permanent Magnet Synchronous Motors With Rotor Eccentricity.
- Author
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Ito, Fumiaki, Takeuchi, Katsutoku, Kotsugai, Takuya, and Matsushita, Makoto
- Subjects
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PERMANENT magnet motors , *ELECTROMAGNETIC forces , *SYNCHRONOUS electric motors , *ROTORS , *MAGNETIC fields - Abstract
This article deals with electromagnetic forces of permanent magnet synchronous motors (PMSMs) with inclined and parallel rotor eccentricity. The electromagnetic forces have the spatial orders of the main components (multiples of pole numbers) and the sideband components when the rotor is eccentric. Although other studies have reported that each amplitude of an upper and a lower sideband is different, the causes of the asymmetry have not been fully investigated. The rotor eccentricity leads to changes in the gap permeance, the working point of the rotor magnets, and the distribution of gap magnetic flux density. By considering these effects in detail, we develop a new analytical expression of electromagnetic force, which expresses the asymmetry of a pairs of sidebands. The expression is compared with 3-D magnetic field analyses of PMSMs with inclined and parallel rotor eccentricity. As a result, it is found that upper sideband amplitudes are larger than lower sideband amplitudes, and the ratio of an upper sideband to the lower sideband of parallel eccentricity is larger than that of inclined eccentricity. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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204. Analysis and Optimization of the Axial Electromagnetic Force for an Axial-Flux Permanent Magnet Vernier Machine.
- Author
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Wang, Quanlin, Zhao, Fei, and Yang, Kuang
- Subjects
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ELECTROMAGNETIC forces , *PERMANENT magnets , *VERNIERS , *FORCE density , *GENETIC algorithms , *STATORS - Abstract
The axial-flux permanent magnet vernier machine (PMVM) is a competitive machine applied in the field of direct-drive which features on low speed and high torque. The rotor of axial-flux PMVM has a tendency to deflect to stator under the effect of the large and unbalanced axial electromagnetic force, which probably results in the collision between rotor and stator. Therefore, this article presents an analysis and optimization of the axial electromagnetic force of the axial-flux PMVM. First, the three-dimensional finite-element model (3-D FEM) is converted to equivalent two dimensional finite-element model (2-D FEM) for further axial electromagnetic force derivation and optimization. Subsequently, four design parameters that are sensitive to the axial electromagnetic force are selected and analyzed for further optimization, which aims to obtain an equal output torque, and reduce the axial electromagnetic force of entire rotor and peak force density of axial electromagnetic force as much as possible. Finally, a Kriging model between the objective functions and design parameters is constructed based on considerable simulation results, and genetic algorithm is applied to search for the proposed optimized result which is ultimately validated by simulation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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205. A Digital Model of the Electrodynamic Acceleration Process in a Coil Gun Devic
- Author
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Andrzej W. HORODEŃSKI and Cezary POCHRYBNIAK
- Subjects
coilgun ,acceleration ,electromagnetic force ,coil ,propulsion ,electromagnetism ,Electronics ,TK7800-8360 ,Chemical engineering ,TP155-156 - Abstract
The subject of this paper is an analysis of the process of applying kinetic energy to a projectile made from a non-magnetic, electrically conductive material and placed inside of an inductance coil live with alternating current. A digital model of an acceleration system was built, comprising a high-current coil and a cylindrical projectile located inside of the coil. Analytical formulas of the three-dimensional distribution of the axial and radial components of the magnetic field generated by the coil were applied [5]. The mathematical model described herein included the projectile and coil three-dimensional system (with the dimensions and distribution of the coil turns), the parameters of the power supply system and their variations, caused by the energy input to the projectile (and including the variation of: coupling coefficient, pulsation, coefficient of attenuation, inductance, and resistance), and the balance of momentum of the projectile and coil system. A system of equations which depicted the projectile and coil system (the law of electromagnetic induction, the Biot-Savart law, electric-to-kinetic energy transfer, and the balance of momentum of the projectile and coil system) was solved with numerical methods. more...
- Published
- 2018
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206. ANALYSIS OF ELECTROMAGNETIC VIBRATION FORCES IN THE ELEMENTS OF THE TURBOGENERATOR STATOR FASTENING TO THE CASE IN NON-NOMINAL OPERATION MODES
- Author
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V. V. Shevchenko, A. N. Minko, and A. V. Strokous
- Subjects
turbogenerator ,load mode ,non-nominal mode ,electromagnetic force ,reactive power ,stator core fastening unit ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Purpose. The purpose of the paper is to determine the value of additional electromagnetic forces (EMF) that are created by the fluxes of scattering of the back of the turbogenerator (TG) stator core in the elements of its fastening to the case when operating in non-nominal modes according to the vibration control data. Methodology. The paper used the theory of electromagnetic fields, the method of polynomial approximation, mathematical modeling in the MathCAD-2000 professional package and the provisions of the general theory of electrical machines. Results. Analytical and numerical calculations of additional EMF values are performed, which were created by the leakage fluxes of the back of the stator core in the elements of fastening of the TG to the case when operating in non-nominal modes, which is determined by the need for night unloading of the power system. The values of these TG forces are established with a change in the output and consumption of reactive power and with a change in voltage. Originality. For the first time for TGs operating in non-nominal modes, the estimation and calculation of additional EMF in the elements of the TG core fastening to the case are carried out, which are created by the leakage fluxes of the back of the stator core and supplement the action of the basic EMF. The definition of these forces is relevant, because turbogenerators of TPPs in Ukraine with a capacity of 200-300 MW are maneuvering capacities and solve the problem of maintaining the power factor of the power system. Practical value. It was found that if the TGs often operate in non-nominal modes, the wear of the stator core fastening systems to the case is more significant than in the case of their operation only in nominal modes. The obtained data will allow to more accurately determine the scope of repair work, draw up schedules for their implementation, determine the locations of the sensors for monitoring, and can be used at the design stage of new machines. more...
- Published
- 2018
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207. Special Relativity
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Helrich, Carl S., Ashby, Neil, Series editor, Brantley, William, Series editor, Deady, Matthew, Series editor, Fowler, Michael, Series editor, Hjorth-Jensen, Morten, Series editor, Inglis, Michael, Series editor, Klose, Heinz, Series editor, Sherif, Helmy, Series editor, and Helrich, Carl S. more...
- Published
- 2017
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208. The RF Plasma Torches
- Author
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Nguyen-Kuok, Shi, Drake, Gordon W F, Editor-in-chief, Babb, James, Series editor, Bandrauk, Andre D., Series editor, Bartschat, Klaus, Series editor, Burke, Philip George, Series editor, Compton, Robert N, Series editor, Gallagher, Tom, Series editor, Joachain, Charles J., Series editor, Lambropoulos, Peter, Series editor, Leuchs, Gerd, Series editor, Meystre, Pierre, Series editor, and Nguyen-Kuok, Shi more...
- Published
- 2017
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209. Understanding, Prospects and Constraints of Emerging Nanotechnology
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Sivakumar, Manickam and Ebenezar, Jeyasingh, editor
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- 2017
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210. A Brief Excursion to Sub-atomic Scales: The Electron, the Muon and the Tau Particle
- Author
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van Holten, Theo and van Holten, Theo
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- 2017
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211. A NEW TYPE OF ELECTROMAGNETICALLY PROPELLED VIBRATION ACTUATOR FOR APPEARANCE INSPECTION OF IRON STRUCTURE.
- Author
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Hiroyuki Yaguchi
- Subjects
ACTUATORS ,PIEZOELECTRIC actuators ,POWER amplifiers ,INFRASTRUCTURE (Economics) ,IRON ,ECONOMIC development - Abstract
Due to economic development, many social infrastructures such as various large structures are being constructed around the world. Inspection and maintenance of social infrastructure such as huge bridges and tanks is one of the most important items in the world. In the present study, a new vibration actuator that extends the principle of operation invented by the authors was proposed and tested. New principle of operation for the actuator capable of reciprocating movement by controlling the phase of two vibration components has been considered. The principle of operation for the actuator was established by a very simple analysis. The experimental results indicate that reciprocating motion can be realized by controlling the phase of the vibration of the two vibration components. Experimental results reveal that this vibration actuator is able to pull a load mass of 190 g and the maximum efficiency of the actuator was about 12.5 % for the case with own-weight. The actuator was confirmed to be able to easily control the direction of movement with two-channel function generator and power amplifier. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
- Full Text
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212. Electromagnetic curves of the polarized light wave along the optical fiber in De-Sitter 2-space S12.
- Author
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Körpinar, Talat and Demirkol, Rıdvan Cem
- Abstract
We review the geometric evolution of a linearly polarized light wave coupling into an optical fiber and the rotation of the polarization plane in De-Sitter 2-space. The optical fiber is assumed to be a one-dimensional object imbedded in the De-Sitter 2-space S 1 2 along with the paper. Mathematically, De-Sitter 2-space S 1 2 is described to be a 2-sphere in a Lorentzian space with positive curvature. Thus, in the De-Sitter 2-space, we have demonstrated that the evolution of a linearly polarized light wave is associated with the Berry phase or more commonly known as the geometric phase. The ordinary condition for parallel transportation is defined by the Fermi–Walker parallelism law. We define other Fermi–Walker parallel transportation laws and connect them with the famous Rytov parallel transportation law for an electric field E , which is considered as the direction of the state of the linearly polarized light wave traveling through the optical fiber in De-Sitter 2-space. Later, we have defined a special class of magnetic curves called by Lorentzian spherical electromagnetic curves (LSEM curves), which are generated by the electric field E along with the linearly polarized monochromatic light wave propagating in the optical fiber. In this way, not only we are able to define a special class of linearly polarized point particles corresponding to LSEM -curves of the electromagnetic field along with the optical fiber in the De-Sitter 2-space, but we can also calculate, both numerically and analytically, the electromagnetic force, Poynting vector, energy-exchanges rate, optical angular and linear momentum, and optical magnetic torque experienced by the linearly polarizable point particles along with the optical fiber in the De-Sitter 2-space. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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213. ANALYSIS AND TESTS OF THE IMPACT OF PERMANENT MAGNETS ON CURRENT INTERRUPTION IN A MEDIUM VOLTAGE ROTARY LOAD BREAK SWITCH.
- Author
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Delić, Sead, Smajkić, Amer, Dullni, Edgar, Santamaria, Sergio, Uzelac, Nenad, and Kapetanović, Mirsad
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ELECTROMAGNETIC forces ,VOLTAGE ,PERMANENT magnets ,DIELECTRIC breakdown ,MAGNETIC fields ,HIGH voltages - Abstract
Copyright of B&H Electrical Engineering is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2021
- Full Text
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214. Development and practice of teaching experimental platform for electric servo vibration.
- Author
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LI Chunbao, CHENG Xudong, YU Rangang, LI Jing, and WU Jianglong
- Abstract
In view of the complexity, abstractness and dullness of the structure vibration theory course, an electric servo teaching experiment platform for simulating structural vibration is developed by using technologies such as the mechanical design, vibration mechanics, computer, etc. The platform is mainly composed of the vibration platform frame, servo control unit, action execution unit, vibration platform, excitation system, high-definition image rapid acquisition system, data acquisition and processing and modal analysis system. It can demonstrate the vibration modes of different types of structures and test the dynamic characteristics, seismic response and modal analysis of structures. The platform can directly capture the whole process of structural vibration, which is helpful to enhance students' sensory understanding of vibration morphology and deepen their understanding of structural vibration theory. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
- Full Text
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215. The Mechanical Analyses of CFETR CSMC Local Components Under the Steady-Operating Condition.
- Author
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Wang, Xianwei, Xu, Aihua, and Wang, Zhaoliang
- Subjects
- *
ELECTROMAGNETIC fields , *PLASMA physics , *ELECTROMAGNETIC forces , *FORCE density , *MAGNETIC fields - Abstract
The R&D of the central solenoid model coil (CSMC) is preparatory toward the final fabrication of the Chinese fusion engineering test reactor central solenoid coil. CSMC is being designed and partly fabricated in the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). During the process, new manufacturing technologies are developed and some design optimization is proposed. Based on the latest design update, a mechanical analysis is launched to verify whether or not the local components can withstand the shock of the complex loads at the CSMC's steady operation stage. The local components here referred to are the current lead joint and joggle. The current lead joint is the key component to transfer the current into coil modules. The joggle is designed to achieve the smooth transition between the different layers during the conductor winding process. The representative current lead joint and joggle are chosen for the mechanical analysis. The electromagnetic analysis is carried out first to calculate the magnetic field and electromagnetic force density by using the software ANSYS. Then, a one-fifth structural analysis model is built to analyze the stress state of the local components under the combination loads. Finally, the local components are evaluated based on the analytical design. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
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216. 永磁辅助同步磁阻电机振动噪声准解析计算 及影响因素分析.
- Author
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韩雪岩, 李春雷, 张新刚, and 王世伟
- Subjects
PERMANENT magnet motors ,ELECTROMAGNETIC forces ,RELUCTANCE motors ,SYNCHRONOUS electric motors ,STRAINS & stresses (Mechanics) - Abstract
Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2020
- Full Text
- View/download PDF
217. 变形镜用高效率音圈驱动器的结构优化设计.
- Author
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曹 朔, 张志高, 赵子云, 顾 虎, 吴晶晶, 朱华新, 苏宙平, 张逸新, and 胡立发
- Subjects
ELECTROMAGNETS ,ELECTROMAGNETIC forces ,FINITE element method ,OPTICAL telescopes ,OPTICAL mirrors ,MAGNETS - Abstract
Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2020
- Full Text
- View/download PDF
218. Crack-Inclusion Problem in a Superconducting Cylinder with Exponential Distribution of Critical Current Density.
- Author
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Zhao, Yufeng and Ji, Pengdong
- Subjects
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CRITICAL currents , *CURRENT distribution , *FUNCTIONALLY gradient materials , *ELECTROMAGNETIC forces , *ELASTIC constants , *CURRENT density (Electromagnetism) - Abstract
In this paper, the crack-inclusion interaction considering the exponential distribution of critical current density is carried out for a functionally graded superconducting cylinder during the zero-field cooling (ZFC) process. By determining the stress intensity factors (SIFs) at the crack tips and performing magnetoelastic stress analysis, the result indicates that the increase of the gradient parameter of critical current density could effectively reduce the stress intensity factors based on the effect of the gradient parameter on the elastic constants ratio of inclusion/matrix, sizes of the inclusion and crack, and the distance between them upon electromagnetic force. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
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219. An Accurate Linearization of Electromagnetic Force of Heteropolar Magnetic Bearings With Redundant Structures.
- Author
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Cheng Xin, Cheng Baixin, Liu Han, and G. M., Allen
- Abstract
Fault tolerance is one of the practical and effective approaches to improve the reliability of magnetic bearings. The linearization of the electromagnetic force (EMF) from the redundant structures is the crucial basis of the design of a fault-tolerant controller. In this paper, we propose an accurate linearization approach for the heteropolar magnetic bearings with redundant structures by solving the Taylor series expansion equation of the current distribution matrix (W) in the nonequilibrium position and introducing a set of displacement compensation matrices to establish a unified accurate EMF model including the controlled current and rotor position. The proposed approach can effectively decrease the EMF error between the actual physical model and the linearized model compared with the existing methods for the consideration of the rotor position. Moreover, the solutions of the current distribution matrix and the relevant optimization approach have been presented on the basis of the proposed approach to help to design a high-performance fault-tolerant controller in the entire rotor displacement range. The numerical results demonstrated the noticeable accuracy advantages of the proposed EMF model. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
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220. Elektromanyetik Silah Matlab/Simulink Modeli.
- Author
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YASUL, Mehmet Fatih and GÜLER, Hasan
- Abstract
Weapons and ammunition technologies are being developed in many different technological innovations in defense industry due to many reasons such as the cost of rocket and gunpowder technologies, the additional load it brings to ammunition, the depletion of energy resources and the rapid development of technology throughout the world. Because of easy to control, simple and renewable source of electromagnetic force, it is widely used in many different areas. This study is analyzed that a weapon mechanism with magnetic area which created electromagnetic force on an object (bullet) to provide the necessary force for acting of the object and this system was tested with MATLAB Simulink. The high-power electromagnetic weapon mechanism converts the potential electrical energy from the power source into kinetic energy with the help of magnetic field, creating a repulsion force to any object (bullet), allowing high-speed firing. With the development of today's defense industry technologies, faster, easier to control and wide range of weapons has accelerated. In this paper, it is obvious that it is one of the important weapon types of the future for electromagnetic weapons. In the present technology, instead of a type of energy that is difficult to control, the force of the projectile, fire, gunpowder etc. is provided with the help of a clean, uninterrupted energy source that is easy to control, that is, magnetic field energy. The aim of this study is to determine the behavioral model of the electromagnetic weapon by means of MATLAB Simulink and to analyze the behavior of projectile velocity, power supply, system components, current, voltage and force and to extract the applicable high efficiency. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
221. Permeance Distribution Function: A Powerful Tool to Analyze Electromagnetic Forces Induced by PWM Current Harmonics in Multiphase Surface Permanent-Magnet Motors.
- Author
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Lv, Yajun, Cheng, Siwei, Ji, Zhongkun, Wang, Dong, and Chen, Junquan
- Subjects
- *
ELECTROMAGNETIC forces , *DISTRIBUTION (Probability theory) , *PULSE width modulation transformers , *PERMANENT magnets , *PULSE width modulation inverters , *MOTORS - Abstract
This article introduces a new method to analyze electromagnetic forces induced by pulsewidth modulation current harmonics in inverter-fed surface permanent-magnet motors. The concept of the permeance distribution function (PDF) is first introduced with its properties and relation to machine inductances fully explained. Utilizing the concept of PDFs, two methods are proposed to calculate the flux distribution on stator boundaries by armature currents and rotor permanent magnets, respectively. By superposing the stator flux distributions from both sources, the final stator electromagnetic force distribution is obtained. The method is validated by finite-element analysis, demonstrating good accuracy and very fast computation time. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
222. A double cantilever beam incorporating cohesive crack modeling for superconductors.
- Author
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Wang, K. F., Wang, Y. Q., Wang, B. L., and Zheng, L.
- Subjects
- *
SUPERCONDUCTORS , *CANTILEVERS , *ELECTROMAGNETIC forces , *COHESIVE strength (Mechanics) , *SUPERCONDUCTING cables , *FINITE element method - Abstract
In this paper, a double cantilever beam (DCB) specimen incorporating cohesive crack is developed for superconductors which have potential applications in high temperature superconducting cables in space solar power station. The cohesive interface is introduced along the crack front of the DCB model under electromagnetic force. The load-separation relation (i.e. the crack opening displacement) is used as the fracture mechanics parameter and the corresponding curves during fracture process are obtained and verified by the finite element numerical method. Results show that the presence of tensile electromagnetic force makes crack propagate easily. Superconductors with small cracks have good adaptability to the oscillation of magnetic fields while that with large cracks are easier to fracture during the descent of the magnetic field. In addition, the ductility ratio of the cohesive interface can significantly increase the fracture strength. The length of fracture zone decreases as the crack length increases. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
223. Fault localization and analysis for a damaged hydrogenerator and a proposal to improve the standard for generator commissioning tests.
- Author
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Akbari, Asghar, Rahimi, Mohammad, Werle, Peter, and Borsi, Hossein
- Subjects
ELECTROMAGNETIC forces ,HYDROELECTRIC generators ,FAULT diagnosis ,WATER power ,TESTING - Abstract
Large power generators, especially hydropower generators with a few hundred megawatts power and a few ten kV voltages, have high inertial power while operating, so they must not only withstand the operating torques and forces during operation, but also the transient forces that may arise at the time of failures, while also taking into account economic considerations. It is worth mentioning that for a large hydroelectric generator, these transient electromagnetic forces are several times the operating forces. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
224. Design and Research of a Three-Phase AC Magnetic Separator for Coal Desulfurization and Ash Reduction.
- Author
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Cao, Min, Chen, Yan, Ma, Chunyan, and Liu, Qiang
- Subjects
MAGNETIC separators ,COAL ash ,DESULFURIZATION of coal ,THREE-phase alternating currents ,DESULFURIZATION ,DESIGN research - Abstract
China's total coal consumption accounts for 50% of total energy consumption. However, every ton of coal in the process of production and use will bring huge losses to the environment. Desulfurization and ash removal of coal have been a continuous focus of researchers in various countries. The three-phase alternating current (AC) magnetic separator is a device for desulfurization and ash reduction of coal based on the principle of generating an alternating magnetic field generated by a three-phase flat linear motor. It is optimized by finite element analysis and its electromagnetic thrust is improved by 114% after optimization. Factors such as current size, magnetic particle size, and installation angle of the device are also analyzed. The simulation results show that the structure design of the three-phase AC magnetic separator is reasonable. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
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225. 涡旋压缩机轴向平衡电磁力的自适应提前跟踪研究.
- Author
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蔡炯炯, 曹 阳, 程楷一, 祝 亮, 王子辉, and 蒋惠忠
- Abstract
Aiming at the requirement of axial gas separation force balance between dynamic and static scroll discs of scroll compressor, the variation law of axial gas separation force of scroll compressor was studied, and the scheme of dynamic force balance using electromagnetic method was put forward.The lag phenomena and corresponding causes in dynamic tracking control of electromagnetic force with iron core were analyzed.After the summarizing of traditional PID controls and the traditional control methodsfor lagging system, the dynamic electromagnetic force control method with advance tracking PID was discussed.The control block diagram was firstly given out, and then its stability was analyzed, the time domain implementation method was also deduced.The influence of different parameters on the control performance was analyzed, after which an adaptive advance tracking PID algorithm was presented to find the optimal number of tracking steps in advance. The experimental platform of electromagnetic mechanism and control system was built, and the control method was verified by experiments. The results show that the dynamic electromagnetic force control method based on the adaptive advance tracking PID algorithm can better track the target curve dynamically. The optimal number of advance steps required varies with frequency, and the optimal steps of advance tracking required for different frequencies can be determined by the proposed adaptive algorithm. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
226. Application of Electromagnetic Field in Anaerobic Biodigestion in Batch Reactors.
- Author
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de Souza Matos, Julios César, Rozenský, Ladislav, ZdeněkVrba, Hansen, Justin Michael, Hájek, Miroslav, Lípa, Jan, Rodrigues, Caroline Varella, Fernandes Luz, Fernanda Giffoni, Avezum Alves de Castro, Marcus César, and Maintinguer, Sandra Imaculada more...
- Subjects
- *
ORGANIC wastes , *ELECTROMAGNETIC fields , *BATCH reactors , *PLANT growing media , *ANAEROBIC digestion , *WASTE treatment - Abstract
Anaerobic digestion processes with biogas production are widely used for organic waste treatment with an emphasis on energy recovery. Some recent studies have demonstrated the influence of magnetism on microbiological activity. These indicate a possible influence on the efficiency of anaerobic digestion. Thus, technologies that act in anaerobic digestion enhancement can contribute to the improvement of treatment of organic compounds. The present study aimed to verify the influence of a constant electromagnetic field on the anaerobic digestion in anaerobic reactors fed with glucose (2 g/L) at 37 ± 2 °C. In each experiment, reactors were operated with a constant electromagnetic field of 5, 7.5, and 10 mT. The inoculum was granular sludge from an anaerobic treatment plant in a non-selective media culture. Biogas production, chemical oxygen demand (COD), and solids removal were measured during the experiment. Results showed differences in methane production of 21.5% and in COD removal of 15% in the tests with an electromagnetic field of 7.5 mT. These results signs for the viability of the application of a constant magnetic field as a biostimulation agent. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
227. Regulation of the welding current magnetic field during electric arc welding of pipes.
- Author
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Shchetinin, S. V., Shchetinina, V. A., and Fedun, V. I.
- Subjects
ELECTRIC welding ,MAGNETIC fields ,ELECTRIC fields ,WELDING ,WELDED joints ,PIPE - Abstract
Mathematical models of magnetic field induction at welding plates and pipes are obtained. The influence of the product shape on induction is established by experiment-calculated way. Magnetic blast during pipe welding increases by more than 10 times due to the concentration of magnetic field lines in a ferromagnetic pipe with high magnetic permeability, the increase in induction by p (3.14) times, the electromagnetic force, acting on an arc and magnetic pressure. A method of onesided high-speed welding of pipes is developed. In such a case, by passing a current opposite to the welding current inside a ferromagnetic pipe, the magnetic blast is prevented, the process stability is enhanced, upward electromagnetic force and magnetic pressure are created that keep the liquid metal from flowing out of the bath. It ensures the formation of quality seams on a flux cushion and an increase in the impact strength of welded joints by 2-2.5 times. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
228. ELECTROMAGNETIC LOCKING DEVICES OF CAR HANDLING UNITS.
- Author
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HRABOVSKÝ, Leopold, FEDORKO, Gabriel, MLÝNEK, Lukáš, and MICHALIK, Peter
- Subjects
ELECTROMAGNETISM ,SOLENOIDS ,FERROMAGNETISM ,TECHNOLOGICAL innovations ,LOCKS & keys - Abstract
This paper contains the design of a testing device, which was constructed for the purposes of checking functional properties of the innovative solutions of variants of electromagnetic locking devices with potentials of replacing current mechanical brakes used for stopping pallets with loaded cars in parking houses developed by the company KOMA - Industry s.r.o. The testing device consists of two positioning tables, whose moveable parts are anchored perpendicular to each other in the frame of the testing device. An electromagnet and a solenoid generating the force needed for stopping the motion of the pallet is connected to the moveable part of the upright positioning table. The brake ramp made of a ferromagnetic material has a hole at its top surface into which the pin of the solenoid is inserted and is attached to the horizontal moveable part of the positioning table. This paper presents holding force values of the electromagnet, which were obtained by experimental measuring on the created testing unit. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
- Full Text
- View/download PDF
229. ELECTROMAGNETIC STIRRING OF METALS IN SPATIALLY ORTHOGONAL MAGNETIC FIELDS.
- Author
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Rashchepkin, A. P., Kondratenko, I. P., Karlov, O. M., Kryshchuk, R. S., Zhiltsov, A. V., and Vasyuk, V. V.
- Subjects
MAGNETIC fields ,ELECTROMAGNETIC forces ,ORTHOGONAL systems ,ELECTROMAGNETIC devices ,LIQUID metals ,MIXING ,INDUCTION heating - Abstract
Copyright of Technical Electrodynamics / Tekhnichna Elektrodynamika is the property of National Academy of Sciences of Ukraine, Institute of Electrodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2020
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230. Study on lateral stability of levitation modules for low- and medium-speed maglev trains.
- Author
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Chen, Xiaohao, Ma, Weihua, Luo, Shihui, and Zou, Ruiming
- Subjects
- *
MAGNETIC levitation vehicles , *LEVITATION , *MATHIEU equation , *EQUATIONS of motion , *ELECTROMAGNETIC forces , *DYNAMIC stability , *DAMPERS (Mechanical devices) - Abstract
In order to study the lateral dynamics stability of the levitation module of low- and medium-speed maglev train, the motion equation is simplified by reasonable assumptions, and the simplest lateral dynamics model is established under the premise of retaining the lateral dynamic characteristics of the levitation module. The model can be characterized by a non-autonomous differential equation with periodic coefficients, which can be transformed into a damped Mathieu equation under certain conditions, with its stability equivalent to that of its Poincaré mapping. The stability of the system can be determined by whether the largest modulus of the eigenvalues of the mapped coefficient matrix is > 1. Then, the sensitivity frequency of the vertical electromagnetic force is obtained by calculating the stability domain of the equation in the parameter space. When the variation frequency of the vertical electromagnetic force is approximately equivalent to the sensitivity frequency, the lateral dynamics model is more likely to be unstable. Besides, the variation amplitude and variation frequency of the vertical electromagnetic force, and other factors such as vehicle load and system damping will also change the stability of the lateral dynamics model. However, due to the uncontrollability of these factors, it is necessary to install a lateral damper for the levitation module to improve the lateral stability. [ABSTRACT FROM AUTHOR] more...
- Published
- 2020
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231. Upgrading recycling of Al–7 wt%Si alloys using electromagnetic force in directional solidification.
- Author
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Tamura, Takuya and Li, Mingjun
- Subjects
- *
DIRECTIONAL solidification , *ELECTROMAGNETIC forces , *HYPOEUTECTIC alloys , *ALLOYS , *CONTINUOUS casting , *ENVIRONMENTAL protection , *ENERGY consumption - Abstract
The highly reactive chemical nature of aluminum makes it production energy-intensive or essentially impossible to extract alloying elements from Al-based liquids. Using molten salt fluxing and electrolysis processes can effectively refine coarse Al scraps. However, the generation of toxic gases and hazardous dross during these processes can cause significant environmental protection challenges and result in notable social concerns. Therefore, the primary recycling of post-consumer Al in industries currently proceeds mainly in a cascade manner, which is not sustainable when considering the Al cycle trends in the coming decades. Herein, we develop a novel process to separate primary Al from the crystallizing liquid when a constant electromagnetic force (EMF) is applied. Using this technique, we successfully upgraded Al–7mass%Si (hereafter, unless specified otherwise) alloy to approximately Al–3.6%Si in directional solidification. The separation mechanism was discussed in terms of the electrical properties of the respective phases during solidification. Fluid flow simulation results were applied to elucidate the separation behavior in the alloy. The upper and lower limits to separate the crystallizing alloy into an Al-rich and Si-rich areas were determined when the controlling factors were clarified, which made it possible to scale up the present laboratory-based setup to an industrial level. Moreover, the energy consumption of the process was slightly higher than that required for remelting only. Using the EMF technique to separate the crystallizing alloy into Al-rich and Si-rich regions did not produce hazardous dross or toxic gases. This energy-saving and eco-friendly process can provide a breakthrough to overcome the "dead metal" crisis and thus realize sustainability by upgrading recycling of post-consumer hypoeutectic Al–Si casting alloys. • Al–7.4 wt%Si can be upgraded to ca. Al–3.6 wt%Si when EMF is imposed in continuous casting. • The Lorentz force controls the co-aggregation of the primary Al solid. • The upper and lower limit of the Al-rich region formation is determined. • EMF is energy-saving for upgrading recycling of hypoeutectic Al–Si alloys. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
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232. Mechanisms of elastic wave generation by EMAT in ferromagnetic media.
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Abderahmane, Abdellahi, Clausse, Bastien, Lhémery, Alain, and Daniel, Laurent
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- *
ELASTIC waves , *MILD steel , *FERROMAGNETIC materials , *ELECTROMAGNETIC forces , *MAGNETIC materials , *PHENOMENOLOGICAL theory (Physics) - Abstract
The present paper deals with the problem of elastic wave generation mechanisms (WGMs) by an electromagnetic-acoustic transducer (EMAT) in ferromagnetic materials. The paper seeks to prove that taking into account all the WGMs must be a general rule to quantitatively predict the elastic waves generated by an EMAT in such materials. Existing models of the various physical phenomena involved, namely magnetic and magnetostrictive, electromagnetic, and ultrasonic, are combined to solve the multiphysics wave generation problem. The resulting model shows that WGMs (i.e. , electromagnetic force, magnetostrictive strain, and magnetic traction) strongly depend on material properties and EMAT design and excitation. To illustrate this, four magnetic materials (nickel, AISI410, Z20C13, and low carbon steel) with similar elastic but contrasting electromagnetic properties are studied. A given EMAT of fixed excitation and geometry yields WGMs with highly different amplitudes in these materials, with a WGM dominant in one material being negligible in another. Experimental results make it possible to validate the accuracy of certain predictions of the model developed. In summary, the present work shows that considering all WGMs is the general rule when working with ferromagnetic materials. Furthermore, it offers a generic model that can be integrated into various numerical tools to help optimize EMAT design and give reliable data interpretation. [ABSTRACT FROM AUTHOR] more...
- Published
- 2024
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233. Evaluation of computational models for electromagnetic force calculation in transformer windings using finite-element method.
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Andrade, Arthur F., Costa, Edson G., Souza, João P.C., Andrade, Filipe L.M., and Araujo, Jalberth F.
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- *
ELECTROMAGNETIC forces , *FINITE element method , *COMPUTATIONAL electromagnetics , *MAGNETIC flux density , *MAGNETISM - Abstract
• For short-circuit analysis, constant-permeability core modeling can be used. • 2D-axisymmetric geometry is not accurate for calculating axial forces. • Simulations using 2D-axisymmetric geometries underestimate radial forces. • Detailed representation results in more accurate EF density and total axial forces. • Only highly detailed geometries allow to determine fault-prone regions. Computer simulations are currently one of the most used methods on transformer's short circuit analysis. For them to be effective, an accurate characterization of the transformer core and geometric representation of windings is essential. Hence, this work investigated the influence of core characterization and different geometric representations on magnetic flux density (MFD) and electromagnetic forces (EF) calculated during short circuits. A comparative study using simulations based on the finite-element method (FEM) were carried out for a 180 MVA transformer model. First, the influence of the nonlinear characteristic of the core B-H curve on EF was analyzed. Then, three two-dimensional (2D) axisymmetric and one three-dimensional (3D) representations were compared. Results indicate there is no significant difference in EF with a core represented by a constant value of permeability. Also, 2D-axisymmetric geometric representations underestimate radial forces and diverge significantly on axial forces in comparison with the 3D representation. Differences up to 99% between the calculated total axial forces were obtained for the analyzed cases. In addition, representations with greater level of detail result in magnetic force density up to 5.5 times greater than that obtained with the simplified representation. [ABSTRACT FROM AUTHOR] more...
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- 2024
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234. Design and Optimization of Halbach Active Suspension Actuator of Vehicle
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Peng, Chong, Zheng, Ling, and Society of Automotive Engineers of China (SAE-China)
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- 2016
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235. The Origin of the Matter in the Universe
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van den Heuvel, Edward, Beech, Martin, Series editor, and van den Heuvel, Edward
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- 2016
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236. Charged Particle Transport in a Collisionless Magnetized Plasma
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Dosch, Alexander, Zank, Gary P., Bartelmann, Matthias, Series editor, Hänggi, Peter, Series editor, Hjorth-Jensen, Morten, Series editor, Jones, Richard A L, Series editor, Lewenstein, Maciej, Series editor, von Löhneysen, H., Series editor, Rubio, Angel, Series editor, Theisen, Stefan, Series editor, Vollhardt, Prof. Dieter, Series editor, Wells, James, Series editor, Zank, Gary P., Series editor, Salmhofer, Manfred, Series editor, Schleich, Wolfgang, Series editor, and Dosch, Alexander more...
- Published
- 2016
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237. Quantum Gravity
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Bahr, Benjamin, Lemmer, Boris, Piccolo, Rina, Bahr, Benjamin, Lemmer, Boris, and Piccolo, Rina
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- 2016
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238. The Strong Interaction
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Bahr, Benjamin, Lemmer, Boris, Piccolo, Rina, Bahr, Benjamin, Lemmer, Boris, and Piccolo, Rina
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- 2016
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239. Timeline of Our Universe
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Bahr, Benjamin, Lemmer, Boris, Piccolo, Rina, Bahr, Benjamin, Lemmer, Boris, and Piccolo, Rina
- Published
- 2016
- Full Text
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240. Separation of Inclusion Particles from Liquid Metal by Electromagnetic Force
- Author
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Shimasaki, Shin-ichi, Takahashi, Koichi, Kanno, Yoshimasa, Taniguchi, Shoji, Weiland, Hasso, editor, Rollett, Anthony D., editor, and Cassada, William A., editor
- Published
- 2016
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241. Removal of Inclusions — A Survey and Comparison of Principles
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Frisvold, F., Engh, T. A., Johansen, S. T., Pedersen, T., Grandfield, John F., editor, and Eskin, Dmitry G., editor
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- 2016
- Full Text
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242. Fault-Tolerant Control of Magnetically-Levitated Rotor with Redundant Structures Based on Improved Generalized Linearized EMFs Model
- Author
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Baixin Cheng, Xin Cheng, Shao Song, Shuai Deng, Rougang Zhou, Yefa Hu, and Huachun Wu
- Subjects
magnetic bearings ,redundant structures ,fault-tolerant control ,electromagnetic force ,Chemical technology ,TP1-1185 - Abstract
Fault tolerance is one of the effective methods to improve the reliability of magnetic bearings, and the redundant magnetic bearing provides a feasible measure for fault-tolerant control. The linearization and accuracy of the electromagnetic force (EMF) from the redundant structures is crucial for designing fault-tolerant controllers. In the magnetic bearing with a redundant structure, the current distribution matrix W is an important factor that affects the accuracy of EMF. In this paper, we improved the accuracy of the EMF model and took the eight-pole symmetrical radial magnetic bearing as the research object. The corresponding displacement compensation matrices have been calculated for the different coils that fail in the magnetic bearing while the rotor is at the non-equilibrium position. Then, we propose a fault-tolerant control strategy that includes displacement compensation. The rigid body dynamics model of the rotor, supported by magnetic bearings with redundant structures, is established. Moreover, to verify the effectiveness of the proposed control strategy, we combined the rigid body dynamics model of the rotor with a fault-tolerant control strategy, and the corresponding simulation has been carried out. In the case of disturbance force and some coils fail in magnetic bearing and compared with the fault-tolerant control that absents the displacement compensation factors. The simulations demonstrate the disturbance rejection of magnetically levitated rotor system can be enhanced. The robustness of the rotor has been improved with the fault-tolerant control strategy proposed in this paper. more...
- Published
- 2021
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243. Investigating a Process of Accelerating Macroscopic Objects in an Eddy-Current Inductance Coil Magnetic Field
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Andrzej HORODEŃSKI, Cezary POCHRYBNIAK, and Kamil NAMYŚLAK
- Subjects
mechanics ,coil gun ,acceleration ,electromagnetic force ,coil ,propulsion ,Electronics ,TK7800-8360 ,Chemical engineering ,TP155-156 - Abstract
The subject of this paper is an analysis of the process of applying kinetic energy to a projectile made of non-magnetic electrically conductive material and located inside an induction coil live with alternating current. An experimental verification was carried out of the analytical conclusions that were pertinent to the design and technology of an inductance coil gun, which is a ranged weapon type. more...
- Published
- 2017
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244. Seismic Analysis of Magnet Systems in Helical Fusion Reactors Designed With Topology Optimization
- Author
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Hitoshi Tamura, Takuya Goto, Junichi Miyazawa, Teruya Tanaka, and Nagato Yanagi
- Subjects
superconducting coil ,fusion magnet ,Electromagnetic force ,Electrical and Electronic Engineering ,seismic analysis ,Condensed Matter Physics ,topology optimization ,Electronic, Optical and Magnetic Materials - Abstract
Superconducting magnets in fusion reactors are subjected to a huge electromagnetic force of >100 MN/m. The magnets have to be sustained with a strong-body structure to avoid high stress and deformation. The total weight of the magnet system in the fusion reactor is estimated to be more than 20,000 tons. We applied topology optimization technique to the magnet support structure to reduce the weight of fusion reactors. Compared with the conventional design, we achieved a weight reduction of >25%. Static and seismic analyses were carried out to validate the soundness of the topology-optimized design. Consequently, the stress against the electromagnetic force in the structure was within the permissible range. It was discovered that using seismic isolation structure can adequately prevent the damage to the magnet system even when directly subjected to a massive earthquake. more...
- Published
- 2022
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245. Seismic Analysis of Magnet Systems in Helical Fusion Reactors Designed With Topology Optimization
- Author
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TAMURA, Hitoshi, GOTO, Takuya, MIYAZAWA, Junichi, TANAKA, Teruya, YANAGI, Nagato, TAMURA, Hitoshi, GOTO, Takuya, MIYAZAWA, Junichi, TANAKA, Teruya, and YANAGI, Nagato
- Abstract
Superconducting magnets in fusion reactors are subjected to a huge electromagnetic force of >100 MN/m. The magnets have to be sustained with a strong-body structure to avoid high stress and deformation. The total weight of the magnet system in the fusion reactor is estimated to be more than 20,000 tons. We applied topology optimization technique to the magnet support structure to reduce the weight of fusion reactors. Compared with the conventional design, we achieved a weight reduction of >25%. Static and seismic analyses were carried out to validate the soundness of the topology-optimized design. Consequently, the stress against the electromagnetic force in the structure was within the permissible range. It was discovered that using seismic isolation structure can adequately prevent the damage to the magnet system even when directly subjected to a massive earthquake., source:H. Tamura, T. Goto, J. Miyazawa, T. Tanaka and N. Yanagi, "Seismic Analysis of Magnet Systems in Helical Fusion Reactors Designed With Topology Optimization," in IEEE Transactions on Applied Superconductivity, vol. 32, no. 6, pp. 1-4, Sept. 2022, Art no. 4900504, doi: 10.1109/TASC.2022.3149731., source:http://doi.org/10.1109/TASC.2022.3149731, identifier:0000-0003-4210-9859 more...
- Published
- 2023
246. Research on a novel drive unit of fast mechanical switch with modular double capacitors
- Author
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Yannan Zhou, Yulong Huang, Weijie Wen, Jingwei Lu, Tiehan Cheng, and Shutong Gao
- Subjects
electromagnetic forces ,circuit breakers ,actuators ,equivalent circuits ,electromagnetic actuators ,drive unit ,fast mechanical switch ,modular double capacitors ,high-voltage direct-current circuit breakers ,mechanical contacts separation time ,hybrid mechanical circuit breakers ,high-voltage system ,DCCB ,electric force ,equivalent circuit method ,ECM ,Thomson coil actuator ,TC actuator ,capacitance discharge ,electromagnetic force ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
The fast mechanical switch is one of the key devices for high-voltage direct-current circuit breakers (DCCB), and the mechanical contacts separation time determines the operating time of hybrid mechanical circuit breakers. With the increasing of the voltage and power levels of DC system, numerous technical challenges begin to emerge. For high-voltage system, the new research and the series arrangements of very fast mechanical switches include designing new drive unit to satisfy larger load mass and longer travel stroke. Aimed to reducing the peak value of electric force, a novel drive unit by using modular double capacitors has been proposed here. Based on the equivalent circuit method (ECM), the mathematical model of Thomson coil (TC) actuator which is the drive unit in fast mechanical switch is established. First, the time sequence of capacitance discharge is studied. Then, the electromagnetic force can be divided into five types in different time sequences, and the characteristics of the electromagnetic force are analysed. Finally, it is concluded that using a combination electromagnetic force with three approximate peaks can reduce the impact of the metal plate, which improve the reliability of the fast switch. more...
- Published
- 2019
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247. Reduction of impact vibration by momentum exchange impact damper using electromagnetic force
- Author
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Masashi KAWATA, Keisuke YAMADA, Susumu HARA, Hideo UTSUNO, Junichi KURATA, and Yoshihiro MURAKAMI
- Subjects
damping ,impact vibration ,vibration control ,momentum exchange ,electromagnetic force ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
In this paper, we proposed a momentum exchange impact damper using a solenoidal coil and a capacitor to suppress impact vibration. Noise and vibration generated by forging machines and press machines have been a serious problem. In order to reduce impact vibration, the momentum exchange impact damper has been studied by many researchers. The basic principle of this damper is based on the momentum transfer during the collisions of three rigid bodies. This impact damper is the most effective when the mass of the damper is equal to the mass of the bed of the forging machine. However, the mass of the damper is usually smaller than the mass of the bed for practical use. In this study, this problem was solved by using a solenoidal coil and a capacitor. The electrical charge stored in the capacitor flows through the solenoidal coil when the impact damper passes through the solenoidal coil using a switch. The electromagnetic force is generated by the electrical current, and the electromagnetic force absorbs the kinetic energy of the host structure. The effectiveness of the proposed method was verified through simulations and experiments. more...
- Published
- 2019
- Full Text
- View/download PDF
248. Vibration control of inverter motor by dynamic absorbers
- Author
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Katsuki MINAMI, Hiroyuki KATAHARADA, Yutaka YOSHITAKE, Yuki KUSHIZAKI, Kota MORIYAMA, and Goh YAMASAKI
- Subjects
vibration control device ,forced vibration ,dynamic absorber ,mortor ,iron stator ,electromagnetic force ,Mechanical engineering and machinery ,TJ1-1570 ,Engineering machinery, tools, and implements ,TA213-215 - Abstract
This paper deals with the quenching problem of electromagnetic vibration of the motor stator in the wide frequency region around the natural frequency using two dynamic absorbers. The iron stator of motor is modeled by circular ring, and two dynamic absorbers are installed on the outside of iron stator to quench the forced vibration caused by the rotating distributed electromagnetic force. The solutions of forced vibration are obtained by the theoretical analysis, and those are compared with the solutions obtained by the finite element method and numerical integration. Following was made clear: (1) By installing two dynamic absorbers which have not only different natural frequencies and different damping ratios but also different masses each other, the iron stator is quenched better than by installing the same dynamic absorbers. (2) It is possible to obtain nearly optimum quenching effect with a pair of dynamic absorbers with equal masses. (3) The mechanism of the above-mentioned vibration quenching method using two different dynamic absorbers is made clear. (4) In the case using the dynamic absorbers those have small values of damping ratios, about 25 degrees is better as angle made by the two dynamic absorbers. (5) The characteristics of resonance curves obtained by the theoretical analysis using ring theory and those obtained by the finite element method and numerical integration agreed well each other. more...
- Published
- 2019
- Full Text
- View/download PDF
249. A Method for Transmitting Spacecrafts in Space with Velocity of at Least 0.01 of the Light Speed Using the Electromagnetic Force of Highly Negative Charged Particles in High Electric Fields
- Author
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Aiad, Mario
- Subjects
Electron Beam ,Electromagnetic Force ,Light Speed ,Classical Physics ,FOS: Mechanical engineering ,FOS: Physical sciences ,Aerospace Engineering ,Spacecraft ,Propulsion ,Attraction Force - Abstract
Many space new missions are on calendar this decade for Moon, Mars and other planets. Some of these missions are depending on simple reliable chemical thrusters but others are depending on the nonchemical advanced propulsion techniques. Although these methods may save time and produce faster journeys, we are still in need for faster methods to travel in space. What about reaching Mars in hours instead of months? Electron beam can do, and so do we; by replacing the electrons with other charged particles using the same electron beam principles. This is a fundamental research on enabling the electron beam to attract objects via its electromagnetic field and to transmit them with an approximate speed reaching at least 0.01 of light speed depending on the dual nature of the electron as a wave and particle, then applying the same principles on larger particles with better characters. The main idea lies in making the electron beam the basic structure in the new process and to build a whole new technology for spacecrafts to travel faster in space with much less cost. The process is based on the cathode ray tube design with consideration of deflection, acceleration and other properties of the electron beam. more...
- Published
- 2023
- Full Text
- View/download PDF
250. Electromagnetic force distribution computations due to switching surge in disc-type winding
- Author
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Nurul Farahwahida Md Yasid, Norhafiz Azis, Mohd Fairouz Mohd Yousof, Jasronita Jasni, Mohd Aizam Talib, and Avinash Srikanta Murthy
- Subjects
Disc winding ,Transformer ,Control and Optimization ,Computer Networks and Communications ,Hardware and Architecture ,Transient ,Signal Processing ,Switching surge ,Electrical and Electronic Engineering ,Electromagnetic force ,Information Systems - Abstract
This manuscript discusses the computation of electromagnetic forces on a disc-type winding due to a standard switching impulse (SSI). First, the resistances, inductances and capacitances (RLC) of a 30 MVA, 33/11 kV disc-type distribution transformer were estimated to obtain the winding equivalent circuit. The transient voltage waveforms for each of the disc layers and corresponding resonances of the windings under the SSI were then obtained in time domains. Next, the axial and radial force distributions in the disc winding due to the SSI were computed. The forces on each disc layer and along the disc windings due to the SSI were computed based on the analytical and numerical methods via the finite element method (FEM) respectively. The non-uniform switching impulse voltage distribution results in non-uniform force distribution along the disc winding. The magnitude of the axially directed force on the disc winding is found to be higher as compared to the radially directed force. more...
- Published
- 2023
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