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The purpose of this study is to develop a novel rectangular linear induction motor as an electromagnetic stirrer (EMS) using analytical followed by a numerical approach. The rectangular linear electromagnetic stirrer (RLEMS) is mainly developed for rectangular slab and billet as the end product.

A two-dimensional analytical approach for evaluating flux density distribution within the mold is established for RLEMS structure. Subsequently, the average stirring force within the mold is estimated from those field variables. The paper presents an analytical and numerical model for calculating the stirring force and counters the end and edge effects of linear-type EMS. Magnetic field and force profile within the mold due to polyphase rectangular stator distribution has been done with the help of Maxwell’s equation with appropriate boundary conditions by using Fourier transform and inverse Fourier transform. Subsequently, a numerical study has been carried out using a coupled thermal and electromagnetic model.

The present study investigates the physical phenomena during the solidification process because of an induced electromagnetic field and is able to extract all the electromagnetic field variables under different operating conditions, and, subsequently, provides an insight into the actual happening within the mold.

It provides the analytical method for solving the stirring force of the proposed new RLEMS structure by addressing the smooth and efficient variation of field and velocity profile near the corner of the mold and improves the quality of end product.

The purpose objective of this study is to identify the friction coefficient and friction effect in electromagnetic upsetting (EMU) high-speed forming process.

Based on numerical simulation and upsetting experiment of 2A10 aluminum alloy bar, the friction coefficient between contact surfaces is obtained by combining the fitting displacement distribution function and the electromagnetic-mechanical coupling numerical model, and the influence of friction effect is analyzed.

The maximum impact velocity and acceleration during EMU are 13.9 m/s and −3.3 × 106 m/s², respectively, and the maximum strain rate is 7700 s⁻¹. The functional distribution relationship between friction coefficient combination (FS, FD) and characteristic parameters [upper diameter (D1) and middle diameter (D2)] is established. The values of FS and FD are 0.1402 and 0.0931, respectively, and the maximum relative error is 2.39%. By analyzing the distribution of equivalent stress and strain, it is found that plastic deformation has obvious zoning characteristics and there is serious failure concentration in the strong shear zone.

Friction coefficient significantly affects stress or strain distributions in material forming process, but it is difficult to obtain friction coefficients through experimental tests in the high-speed forming process. In this paper, a multi-field coupling numerical model is proposed to determine friction coefficients and applied to the electromagnetic impact loading process (a high-speed forming process).

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0154/

The purpose of this study is to develop an efficient model to solve the electromagnetic forward problem using a novel semi-analytical approach to compute the electromagnetic fields because of the presence of a scatterer.

The proposed model involves a novel formulation of a complete orthonormal set of radiating/nonradiating polarization currents. Furthermore, an integral equation-based representation is derived, and the appropriate boundary conditions are imposed to get the scattered electromagnetic field. An error term is introduced to evaluate the obtained results.

The proposed model was tested using several examples at different frequencies. The results of this study show that the novel representation exhibits fast convergence behavior and achieves highly accurate results, when compared to the results provided by the transmission line method.

The derived formulations presented in this study are significant in the electromagnetic forward modelling field because of the meaningful physical representation they provide. This is an important aspect that leads to precise calculation of electromagnetic fields for various applications.

Solves a coupled electromagnetic‐mechanical problem ‐ that of a cantilevered conductive plate in crossed steady and time‐varying magnetic fields ‐ by using a semi‐analytical method and an eddy current model. Assumes that the magnetic flux variation induces two electromotive forces to the plate; one due to the time‐varying magnetic field and the other to the plate movement in the steady magnetic field. Considers two equivalent LR circuits and notes that the superposition of their currents yields the total circulating current in the plate. Couples this electromagnetic model to the one‐dimensional beam bending model, adopted for the structural analysis of the problem and derives the system of the coupled electromagnetic‐mechanical equations. Calculates analytically some of the parameters involved in these equations so that the numerical computation of the remaining unknowns is very rapid. Concludes that the results are in agreement with the experiment and with results obtained by numerical methods treating, in three dimensions, the electromagnetic aspects of the problem. Notes that the fully numerical methods are very much CPU time consuming.

The aim of this paper is to use an analytical multi‐physical model – electromagnetic, mechanic and acoustic – in order to predict the electromagnetic noise of a permanent magnet synchronous machine.

The aim of this work is to develop and use an analytical multi‐physical model – electromagnetic, mechanic and acoustic – of a synchronous machine with permanent magnets. The complete model is coded in order to predict acoustic noise. A study of sensitivity is presented in order to deduce the influential – or significant – factors on the noise. For that, the technique of the experimental designs is used. More particularly, the modeling of the noise will be achieved due to the new “trellis” designs.

Three models are presented: electromagnetic, mechanical of vibration and acoustic. For each of them, comparisons with finite element method and experiments have been made. Several response surfaces are given; they represent the noise according to influential factors, with respect to different speeds of the machine. These surfaces are useful to deduce the parts of the design space to avoid.

Different multi‐physical aspects are considered: electromagnetic, mechanic and acoustic phenomena are taken into account due to a single analytical model. The experimental design method is the privileged tool used to make the complex relationships between the main variables appear.

In this paper, modeling of the XLPE cable for electromagnetic signature study at a far distance is proposed. The paper aims to discuss these issues.

Due to the very small ratio of the dimensions of cables to the dimensions of the whole system, using actual geometry of the cables with all layers in this study causes deformation of the cable's model. Therefore, multi-dipole modeling is used for modeling the cables.

This model includes specific voltages and currents in lines and nodes, respectively. Radiated electric and magnetic fields at a far distance are selected as the index of appropriateness of the model.

In order to investigate the accuracy of the model, various configuration of the cable is studied. Additionally, coupling of the cable with an electrical machine is investigated. They all show that the equivalent models can be used in place of the actual model for signature studies.

The purpose of this paper is to determine the impact of human age on the distribution of electric field and absorbed energy that originates from a mobile phone.

This research was performed for frequencies of 900, 1800 and 2100 MHz, which are used in a mobile communication system. To obtain the most accurate results, 3 D realistic model of the child’s head has been created whereby the dimensions of this model correspond to the dimensions of a seven-year-old child. Distribution of the electric field and specific absorption rate (SAR) through the child’s head was obtained by numerical analysis based on the finite integration technique.

The results discover that amount of absorbed energy is greater in the surface layers of the child’s head model when the electromagnetic (EM) characteristics of tissues are adjusted for the child. This deviation corresponds to different EM characteristics of biological tissues and organs of an adult person compared to a child.

The study deals with penetrated electrical field and absorbed EM field energy. There is space for further studies of other EM field effects (e.g. thermal effects).

The analysis of obtained results leads to idea that mobile phones and devices aimed for children using should be modified to provide SAR values inside prescribed standards.

The obtained results are foundation for future research on influence of EM fields of mobile devices on human health.

The proposed procedure offers the model for accurate estimation and quality analysis of SAR and EM field distribution inside child head tissue.

The aim of this paper is to develop network models of an electromagnetic field containing both eddy and displacement currents. The proposed network models provide good physical insight, help understanding of complicated electromagnetic phenomena and aid explanation of methods of analysis of electromagnetic systems.

The models consist of magnetic and electric networks coupled via sources. The analogy between the finite element method and the loop and nodal formulations of electric circuits is emphasised. The models include networks containing branches associated with element edges (edge networks) or facets (facet networks).

Methods of determining mmf sources of magnetic networks from loop and branch currents in electric circuits, as well as emf sources in electric networks on the basis of the rate of change of loop and branch fluxes in electric networks, have been carefully considered. The models are general and allow creation of networks of electromagnetic systems containing non‐homogenous materials and multiply‐connected conducting regions.

The presented analogies between the finite element formulation and the equivalent network models not only facilitate understanding of the methods of field analysis but also help to formulate efficient computational algorithms.

Disturbing vibrations and noise of electrical machines are gaining impact. The paper aims to focus on the necessity of estimating the electromagnetic, structure‐dynamical, and acoustic behaviour of the machine during designing and before proto‐typing.

An adequate tool is numerical simulation applying the finite‐element method (FEM) and the boundary‐element method (BEM) allowing for the structured analysis and evaluation of audible noise also caused by manufacturing tolerances.

The simulated results show good accordance to measurement results. The methods and simulation tools allow the analysis and evaluation of every type of energy converter with respect to its electromagnetic, structure‐dynamical and acoustic behaviour.

The methods developed and proved can be applied to any electromagnetic device in general.

The purpose of this paper is to investigate the use of multidisciplinary optimization (MDO) formulations within space‐mapping techniques in order to reduce their computing time.

The aim of this work is to quantify the interest of using MDO formulations within space mapping techniques. A comparison of three MDO formulations is carried out in a short time by using an analytical model of a safety transformer. This comparison reveals the advantage of two formulations in terms of robustness and computing time among the three MDO formulations. Then, the best formulations are investigated within output space mapping, using both analytical and FE models of the transformer.

A major computing time gain equal to 5.5 is achieved using the Individual Disciplinary Feasibility formulation within the output space‐mapping technique in the case of the safety transformer.

The MultiDisciplinary Feasibility formulation is the common formulation used within space‐mapping technique because it is the most conventional way to perform MDO. The originality of this paper is to investigate the Individual Disciplinary Feasibility formulation within output space‐mapping technique in order to allow the parallelization of calculation and to achieve a major reduction of computing time.