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In the proposed paper a model permitting force analysis in tubular induction devices is presented. A hybrid finite element‐boundary element method using time stepping is used to compute the electromagnetic force; this force is introduced in the mechanical equation to determine the acceleration. Numerical values are compared to experimental values.

In the applications of FEM. a compromise between the accuracy and the computation cost is often required, especially when 3D cases are concerned Adaptive mesh refinement is a good answer to this demand.

We present in this paper an efficient finite element analysis for different types of waveguides . The computations are performed with “edge elements” . These finite elements avoid all the “spurious modes”, the non‐physical numerical fields obtained from the solution of eigenvalue problems with classical finite elements formulations.Both dielectric‐loaded waveguides and ridged waveguides (waveguides with sharp edges) are analyzed. Comparisons of our results with previously published ones show theaccuracy of the numerical technique.

This paper presents a hybrid finite element — boundary element method for the steady state thermal analysis of energy installations. The coupling of the two techniques is presented: finite elements are used in a bounded region containing thermal sources while the complementary domain is treated with boundary elements. With such a combination the number of unknowns is reduced and an accurate prediction of temperature is obtained. As an example, the temperature rise is computed for the case of three power cables laid in a thermal backfill: the finite element method (FEM) is used for the cables and the backfill while the homogeneous soil is taken into account with the boundary element method (BEM).

This paper aims to give a perspective about the variety of techniques which are available and are being further developed in the area of coupled field formulations, with selective bibliography and practical examples, to help postgraduate students, researchers and designers working in design or analysis of electrical machinery.

This paper reviews the recent trends in coupled field formulations. The use of these formulations for designing and non‐destructive testing of electrical machinery is described, followed by their classifications, solutions and applications. Their advantages and shortcomings are discussed.

The paper gives an overview of research, development and applications of coupled field formulations for electrical machinery based on more than 160 references. All landmark papers are classified. Practical engineering case studies are given which illustrate wide applicability of coupled field formulations.

Problems which continue to pose challenges to researchers are enumerated and the advantages of using the coupled‐field formulation are pointed out.

This paper gives a detailed description of the application of the coupled field formulation method to the analysis of problems that are present in different electrical machines. Examples of analysis of generators and transformers with this formulation are presented. The application examples give guidelines for its use in other analyses.

The coupled‐field formulation is used in the analysis of rotational machines and transformers where reference data are available and comparisons with other methods are performed and the advantages are justified. This paper serves as a guide for the ongoing research on coupled problems in electrical machinery.

In analysing coupled electromagnetic thermal behaviours in electrical devices one of the main difficulties is related to the uncertainties of thermal parameters. The authors present, in this work, a technique using the method of experimental designs for the identification of thermal parameters necessary for a coupled finite element model analysing the magneto‐thermal behaviour of an electromagnetic device.

Benchmark problem 7 of the TEAM workshop consists of an asymmetrical conductor with a hole. 17 computer codes are applied, and 25 solutions are compared with each other and with experimental results for eddy current densities and flux densities. Most of the codes were found to give satisfactory solutions.

This paper deals with the numerical simulation of eddy current distributions in non‐stationary geometries with sliding interfaces. We study a system composed of two solid parts: a fixed one (stator) and a moving one (rotor) which slides in contact with the former. We also consider a two‐dimensional mathematical model based on the transverse electric formulation of the eddy current problem whose approximation is performed via the mortar element method combined with the standard linear finite element discretization in space and an implicit first order Euler scheme in time. Numerical results underline the influence of the rotor movement on the current distribution and give an estimate of the power losses with respect to the rotor angular speed.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

To extend the field application of numerical simulation, it is necessary in many applications to consider the electric circuit. Usually the magnetic equations are solved using the 3D finite element method which implies the solution of a non‐linear equations system. To solve the electric circuit equations a mesh or a state variable method can be used. It may be noted that the electric equation system obtained with these methods can also be non‐linear in presence of semi‐conductor components in the electric circuit. If the interaction between the magnetic and electric circuits is important both non‐linear matrix systems must be solved simultaneously.