A5052654524- Electromagnetic Simulation and Numerical Methods
- Magnetic Properties and Applications
- Non-Destructive Testing Techniques
- Magnetic confinement fusion research
- Electromagnetic Scattering and Analysis
- Numerical methods in engineering
- Electric Motor Design and Analysis
- Fusion materials and technologies
- Advanced Numerical Methods in Computational Mathematics
- Model Reduction and Neural Networks
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Metallurgy and Material Forming
- Plasma Diagnostics and Applications
- Vibration and Dynamic Analysis
- Laser-Plasma Interactions and Diagnostics
- Mechanical stress and fatigue analysis
- Electromagnetic Compatibility and Measurements
- Magnetic Bearings and Levitation Dynamics
- Induction Heating and Inverter Technology
- Microstructure and Mechanical Properties of Steels
- Magnetic Properties of Alloys
- Nuclear reactor physics and engineering
- Real-time simulation and control systems
- Gas Dynamics and Kinetic Theory
Mitsubishi Electric (Japan)
2000
Mitsubishi Heavy Industries (Japan)
1997
Mitsubishi Group (Japan)
1985-1995
Japan Atomic Energy Agency
1976-1989
The calculation of transient 3-D eddy current using edge elements in the modified A-method is presented. Quadratic 36-edge on 20-node isoparametric are proposed. Specifically, test problems a square plate and hollow sphere solved with linear 12-edge quadratic elements, results compared analytical solutions. two types agree well each other solution, demonstrating applicability these for eddy-current calculation. spatial distributions magnetic field interpolated by shape functions approximated...
This paper presents a novel method for analyzing transient magnetic fields in laminated iron cores. It is based on the finite-element and newly developed homogenization applied to model lamination effectively. The homogenized constitutive relations, of which approximation only applicable low-frequency problems, are derived analytically, neglecting eddy currents induced by time-varying fluxes parallel lamination. loss due neglected estimated postprocessing state utilizing obtained field...
A novel model order reduction method for efficient analysis of linear eddy-current problems is proposed in which the quasi-static electromagnetic fields are expressed by a weighted sum sequence static electric- and magnetic-field modes. The modes calculated sequentially electric magnetic computations using conventional finite-element method, time-dependent weights voltages currents an equivalent Cauer ladder network problem. In this paper, formulation numerical test problem presented,...
A coupled finite element-boundary element method is applied to three-dimensional eddy-current problems. The magnetic vector potential and scalar phi are adopted for the formulation. used in conducting region, while boundary exterior vacant region. symmetric linking chosen coupling procedure. calculations show good agreement with analytical results obtained by other numerical methods.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A line search was combined with the Newton-Raphson method to accelerate convergence of iterative calculation in nonlinear magnetic field analysis. As a for determining step size update, minimization an energy functional and square 2-norm residual obtained from finite-element discretization investigated. It demonstrated that is superior viewpoint computational cost. The effective even vector potential formulation, which said be stable usually.
This paper proposes a novel method for the improvement of convergence to steady state in time-periodic transient nonlinear eddy-current analyses. The proposed method, which is based on finite element and singularity decomposition-explicit error correction can extract poorly converged components corresponding large time constants an analyzed system. extracted efficiently accelerates state. Numerical results verify effectiveness method.
A centrifuge injector that repetitively fires 1.3 mm deuterium pellets (1 torr⋅L per pellet) at a rate of 32 second was used to build up and maintain Doublet III 2.4 MW neutral-beam-heated limiter discharge line-averaged density 1 × 1014 cm−3. When compared conventional gas-fuelled plasma similar density, the pellet-fuelled characterized by factor-of-three reduction in edge neutral recycling, centrally peaked profile, 70% increase global energy confinement, tenfold fusion reaction rate.
The Darwin model for electromagnetic quasistatic (EMQS) field analysis is of particular interest the power electronic devices, such as transformers and wireless transfer systems. This an approach that neglects second derivative term in time displacement current considers electrostatic field. approximation allows conventional techniques magneto-quasistatic (MQS) analysis, considering nonlinear magnetic material properties coupled circuit to be appropriated, capacitance effects included....
A new method using a regular coupling mesh is proposed for problems involving movement in the FEM analysis of electric machines edge elements. The fixed and moving regions are coupled through mesh. approach allows simple independent generation rotor stator meshes. An induction motor with skewed slots analyzed 3-D by this results compared to measurements. authors investigated effects end-rings on characteristics motor, which difficult analyze 2-D analysis. good agreements between numerical...
In the quasi-static magnetic field calculation, equation is indefinite when we use edge elements without gauge condition by tree and co-tree decomposition. The convergence property of incomplete Cholesky conjugate gradient (ICCG) method investigated in FEM A-/spl phi/ formulation using elements. Even continuity source current density not satisfied strictly, can obtain converged solutions including error discontinuity ICCG. Also a two scalar potentials to impose divergence-free mesh proposed.
Three-dimensional eddy current equations are formulated in terms of a magnetic vector potential A and an electric scalar V the conductive regions reduced Omega nonconductive region. finite-element computer code, EDDY3DT, has been developed using this A-V formulation. Application to test problems comparison with analytical solutions or results by other methods show that formulation is effective for involving anisotropic discontinuous conductivities, cracks, holes.< <ETX...
The conventional finite-element method (FEM) deteriorates the convergence characteristic of incomplete Cholesky conjugate gradient (ICCG) in magnetic field analyses when there are extreme thin elements meshes. is drastically improved by a proposed method, where common unknown variables simply added to near parallel edges. number unknowns increased, but rank equation not changed and condition matrix becomes better. for presented paper an application ldquosingularity decomposition...
In this article, a method for motor model order reduction is developed using the Cauer ladder network (CLN). The analyzed domain decomposed into stator and mover domains, where multiport CLN of each constructed independently other. two domains are connected through electromagnetic field modes at boundary. boundary condition derived from coordinate transformation. reduced accurately reconstructs induction property affected by slot harmonics.
A general model for the coupled analysis of magneto-mechanical systems is developed by minimizing continuum energy functional system using calculus variation. This approach, which in contrast with traditional approach after discretization, allows use strain and stress tensors, vector identities divergence theorem, results governing equations three coupling terms; magnetic tensor, magnetostriction reluctivity. The uses information contained set experimental curves dependent on to calculate...
A new type of second order edge elements for simplexes (triangles and tetrahedra) is proposed. The element geometrically symmetric the shape functions are orthogonal to each other in integrals tangential components on edges. number nodes edges 14 24 a tetrahedral element. proposed validated by eigenmode calculations cavity using newly developed method solve eigenvalue problems with large matrices. Highly accurate eigenvalues calculated elements.
This paper proposes a novel effective method for open boundary problems by using the finite-element (FEM) with new formulation of infinite edge element. We developed element adopting characteristic conventional elements, resulting in sparse and symmetric matrix. proposed technique has advantage drastically reducing computational burden keeping analyses' accuracy. Some numerical examples which demonstrate validity are presented.
This paper develops the time-periodic explicit error correction (TP-EEC) method for convergence acceleration to a steady state in transient analysis of synchronous machines. The methods deal with movement rotor and different time-periodicity fixed moving parts mesh are investigated. Furthermore, we propose novel TP-EEC based on polyphase time periodic condition. Numerical results verify effectiveness developed methods.
Analyses of eddy currents and forces in conductors with motion are presented. The relative between source magnetic fields has been newly introduced two codes (the finite element method the circuit method) by moving field keeping conductor still. For verification method, problems a rotating circular plate coil over rectangular calculated results compared analytical solutions. good agreement solutions obtained without numerical instability even at higher Peclet number.< <ETX...
This paper describes a large-scale and highly accurate magnetostatic field analysis targeting magnetic shield. The hybrid finite element–boundary element method the moment do not require mesh division for free space can easily treat nonlinearity of property. Therefore, these methods are considered very effective shield which has high aspect ratio size scale to thickness. However, large memory computational time have been required due dense matrices generated by those integral-based...
This paper proposes an orthogonalization of the Hilbert matrix in element matrices infinite edge elements. The validity is demonstrated previous researches, but results extremely slow convergence ICCG method, especially when using higher order expansions. proposed technique improves drastically and it makes elements practical electromagnetic FEM analysis open boundary problems quasi-static magnetic fields.