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Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

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.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

The paper presents the analysis of magnetic field that surrounds the power transformer after it has been switched off. The purpose of this paper is to determine the possibility of defining the residual fluxes in the legs of the transformer based on the measurement of this field. It was also intended to determine the type and the location of magnetic sensors.

Numerical analysis of the magnetic field was performed. A three-dimensional model of the transformer’s magnetic core was created in the Flux 3D simulation program. The analysis was concerned with an oil-filled transformer and a dry transformer. The magnetic field of Earth was taken into account.

The research has shown that magnetic induction of the leakage field produced by residual magnetization of the core is comparable to the magnetic induction of the Earth’s field. It was also found that the measurement of the magnetic induction should be performed as close as possible to the core. The interior of the tank turned out to be a convenient space for the placement of the sensors.

The influence of external ferromagnetic objects, and devices generating magnetic field, on the measurement was not considered. It should be taken into account in the future work.

On the basis of the analysis, it was proposed to measure the magnetic induction vector of the leakage field at three points. The sensors should be placed in front of the columns at a position that is half of their height. The measurement can be performed with satisfactory accuracy by sensors located on the surface of the windings.

The purpose of this paper is to present computer simulations of ship’s magnetic signatures using a new thin plate boundary condition implemented in the Opera 3D 18R2 programme. This paper aims to check the magnetic signatures’ numerical calculations precision of objects using the thin plate boundary conditions and analysis of the magnetic signature of ship with a degaussing system and with and without inner devices.

The ferromagnetic sphere and cube with and without the thin plate boundary condition were compared. The computer results of the magnetic field of a sphere were compared with an analytical solution. A superstructure, decks, hull and bulkheads of a corvette were modeled. An analysis of ship’s magnetic field with consideration of inner ferromagnetic devices and with degaussing system was carried out.

The results of the analytical and numerical comparative analysis of magnetic field of cube and sphere have shown that the thin plate boundary condition is a good method for analysis of magnetic signatures of thin-walled objects. The computer simulations of the corvette model have shown that for relative magnetic permeability of a few hundred range the influence of inner ferromagnetic devices on the ship’s magnetic signature is negligible. The thin plate boundary condition is also good method for calculation of the ship magnetic signature with degaussing system and for optimization currents of coils.

The calculation time of ship’s magnetic field with the thin plate boundary condition bears resemblance to the ship model with layers of steel.

The purpose of this paper is to reduce computation time of magnetic characteristic analysis considering 2D vector magnetic properties.

The paper proposes a complex E&S modelling with assumption that both flux density and field strength waveforms are sinusoidal. The computation time of the complex E&S modeling becomes 1/10 in comparison with one of the conventional E&S modeling. This modeling is applicable up to 1.4 T of the local magnetic flux density condition in the case of non‐oriented magnetic materials.

In the results of the magnetic field analyses of a linear‐induction motor model core by means of the finite element method taking account of the complex E&S modeling, the distributions of the flux density and the field strength were able to be approximately analyzed and their phase differences in space were represented. The results of the magnetic characteristic analysis of the linear‐induction motor showed that the teeth‐end shape had large influences on the thrust and cogging.

This technique helps to know approximately local vector magnetic properties in core materials. This modeling is very useful for magnetic core design taking account of the simplified 2D vector magnetic properties.

The method presented in this paper enables expression of the simplified 2D vector magnetic properties in magnetic field analyses. The computation time can be considerably reduced in comparison with the conventional method.

This paper aims to investigate the thermal performance of equivalent square and circular thermal systems and compare the heat transport and irreversibility of magnetohydrodynamic (MHD) nanofluid flow within these systems.

The research uses a constraint-based approach to analyze the impact of geometric shapes on heat transfer and irreversibility. Two equivalent systems, a square cavity and a circular cavity, are examined, considering identical heating/cooling lengths and fluid flow volume. The analysis includes parameters such as magnetic field strength, nanoparticle concentration and accompanying irreversibility.

This study reveals that circular geometry outperforms square geometry in terms of heat flow, fluid flow and heat transfer. The equivalent circular thermal system is more efficient, with heat transfer enhancements of approximately 17.7%. The corresponding irreversibility production rate is also higher, which is up to 17.6%. The total irreversibility production increases with Ra and decreases with a rise in Ha. However, the effect of magnetic field orientation (γ) on total EG is minor.

Further research can explore additional geometric shapes, orientations and boundary conditions to expand the understanding of thermal performance in different configurations. Experimental validation can also complement the numerical analysis presented in this study.

This research introduces a constraint-based approach for evaluating heat transport and irreversibility in MHD nanofluid flow within square and circular thermal systems. The comparison of equivalent geometries and the consideration of constraint-based analysis contribute to the originality and value of this work. The findings provide insights for designing optimal thermal systems and advancing MHD nanofluid flow control mechanisms, offering potential for improved efficiency in various applications.

The purpose of this paper is to introduce a numerical calculation method to study the uniformity of the magnetic field in a cold crucible used for directional solidification (DS) and provide information for designing a cold crucible that can induce a uniform magnetic field.

To obtain the characteristics of the magnetic field in a cold crucible and its influence on the directional solidification processing, based on experimental verification, 3‐D finite element (FE) models with different crucible configuration‐elements and power parameters were established to study the uniformity of the magnetic field in a cold crucible. In addition, different TiAl ingots were directionally solidified with different cold crucibles, and the solid/liquid (S/L) interfaced were examined to investigate the effect of the magnetic field on the macrostructure of those ingots.

The uniformity of the magnetic field in a given domain can be quantitatively analyzed by statistical methods. Numerical calculation results showed that the uniformity of the magnetic field can be improved by optimizing the crucible configuration and adopting lower frequency. Better uniformity of the magnetic field in a cold crucible is beneficial to directional solidification.

The calculation of the uniformity of the magnetic field is proposed as a method for quantitative study of the distribution characteristics of the magnetic field in a cold crucible. The relationship between the S/L interfaces of TiAl ingots and the uniformity of the magnetic field is initially characterised; additionally, techniques for improving the uniformity of the magnetic field in a cold crucible are suggested.

For this purpose, a linear stability analysis based on the Navier–Stokes and Maxwell equations is made leading to an eigenvalue differential equation of the modified Orr–Sommerfeld type which is solved numerically by the spectral collocation method based on Chebyshev polynomials. Unlike previous studies, blood is considered as a non-Newtonian fluid. The effects of various parameters such as volume fraction of nanoparticles, Casson parameter, Darcy number, Hartmann number on flow stability were examined and presented. This paper aims to investigate a linear stability analysis of non-Newtonian blood flow with magnetic nanoparticles with an application to controlled drug delivery.

Targeted delivery of therapeutic agents such as stem cells and drugs using magnetic nanoparticles with the help of external magnetic fields is an emerging treatment modality for many diseases. To this end, controlling the movement of nanoparticles in the human body is of great importance. This study investigates controlled drug delivery by using magnetic nanoparticles in a porous artery under the influence of a magnetic field.

It was found the following: the Casson parameter affects the stability of the flow by amplifying the amplitude of the disturbance which reflects its destabilizing effect. It emerges from this study that the taking into account of the non-Newtonian character is essential in the modeling of such a system, and that the results can be very different from those obtained by supposing that the blood is a Newtonian fluid. The presence of iron oxide nanoparticles in the blood increases the inertia of the fluid, which dampens the disturbances. The Strouhal number has a stabilizing effect on the flow which makes it possible to say that the oscillating circulation mechanisms dampen the disturbances. The Darcy number affects the stability of the flow and has a stabilizing effect, which makes it possible to increase the contact surface between the nanoparticles and the fluid allowing very high heat transfer rates to be obtained. It also emerges from this study that the presence of the porosity prevents the sedimentation of the nanoparticles. By studying the effect of the magnetic field on the stability of the flow, it is observed that the Hartmann number keeps the flow completely stable. This allows saying that the magnetic field makes the dissipations very important because the kinetic energy of the electrically conductive ferrofluid is absorbed by the Lorentz force.

The originality of this paper resides on the application of the linear stability analysis for controlled drug delivery.