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The standard Newton iteration scheme to solve a non‐linear system of equations obtained from the finite element methods is based on the updating of the field dependent element reluctivity. Usually, the manufacturer of the ferromagnetic material provides a BH‐characteristic as diagram or in the form of a table of data samples. The influence of the material properties, in particular their accurate numerical representation, is significant for the rate of convergence during the Newton iterations. Here, a numerical optimization aiming at a technically smooth non‐linear characteristic is performed to obtain a higher rate of convergence of the Newton iteration scheme.

The calculation of magnetic shielding with ferromagnetic material by an effective reluctivity method and a time step method based on the finite element calculation is investigated. The calculation results of both methods are compared with measurement results and with each other in order to check their reliability and accuracy. It turns out that both methods give similar results for the field inside the shielding material, whereas in the surrounding air the effective reluctivity method gives more accurate results than the present time step method.

The purpose of this paper is to develop a fast and accurate analytic model function for the single-valued H-B curve of ferromagnetic materials, where hysteresis can be disregarded (normal magnetization curve). Nonlinear magnetoquasistatic simulations demand smooth monotone material models to ensure physical correctness and good convergence in Newton's method.

The Brauer model has these beneficial properties, but is not sufficiently accurate for low and high fields in the normal magnetization curve. The paper extends the Brauer model to better fit material behavior in the Rayleigh region (low fields) and in full saturation. Procedures for obtaining optimal parameters from given measurement points are proposed and tested for two technical materials. The approach is compared with cubic spline and monotonicity preserving spline interpolation with respect to error and computational effort.

The extended Brauer model is more accurate and even maintains the computational advantages of the classical Brauer model. The methods for obtaining optimal parameters yield good results if the measurement points have a distinctive Rayleigh region.

The model function for ferromagnetic materials enhances the precision of the classical Brauer model without notable additional simulation cost.

The purpose of this paper is to promote practical methods for the numerical modelling of hard magnetic materials and soft ferromagnetic materials in an engineering context (design of electrical machines).

Objectives achieved by the use of a practical, semi‐empirical material model that needs modest material data and computer resources. Methods: a focused theoretical specification and algorithm development; use of actual material data for algorithm validation; incorporation in commercial engineering software as a test harness. Approach: a practical engineering scheme using a macroscopic material model based on readily available materials data. Scope: numerical model of hard magnetic and soft ferromagnetic materials; scalar and vector hysteresis, major and minor loops.

The limited practicality of much of the literature, especially vector hysteresis; successful use of the model in an existing non‐linear numerical solver; energy conservation gives confidence in the results; the electric motor provides a good validation test case.

Possible future research: application to more complicated material properties such as magneto‐relaxation.

The paper extends the scope of computer‐aided engineering design of electrical machines. The impact on the developer: increased sale of an engineering software product. The impact on the design engineer: more efficient designs, reduced prototyping, reduced technical risk.

The algorithm that provides an effective material model; the focus on the practical issues of data and computational resources; the implementation of a theoretical construct in a large‐scale engineering design program. The value is to designers of electrical machines.

Manufacturing processes, such as laminations, may introduce uncertainties in the magnetic properties of materials used in electrical machines. This issue, together with magnetization errors, can cause serious deterioration in the performance of the machines. Hence, stochastic material models are required for the study of the influences of the material uncertainties. The purpose of this paper is to present a methodology to study the impact of magnetization pattern uncertainties in permanent magnet electric machines.

The impacts of material uncertainties on the performances of an interior permanent magnet (IPM) machine were analyzed using two different robustness metrics (worst-case analysis and statistical study). In addition, two different robust design formulations were applied to robust multi-objective machine design problems.

The computational analyses show that material uncertainties may result in deviations of the machine performances and cause nominal solutions to become non-robust.

In this paper, the authors present stochastic models for the quantification of uncertainties in both ferromagnetic and permanent magnet materials. A robust multi-objective evolutionary algorithm is demonstrated and successfully applied to the robust design optimization of an IPM machine considering manufacturing errors and operational condition changes.

In this paper the kinetic behavior of a non‐magnetic cube, plated on two opposite sides with ferromagnetic coating, situated on a horizontal plane surface and immersed in a homogeneous magnetic field is investigated. The created magnetic torque is determined, the involved field quantities are computed applying the integral equation method taking into account the hysteresis of the ferromagnetic coating by a non‐linear iterative procedure based on the Piccard‐Banach fixed point technique. Considering the friction between the piece and the plane surface the equation of motion is solved. The magnetic field strength necessary to rotate the piece in a required direction is determined.

Recent advances in solid state power conversion, specially in the high frequency domain, have shown the need for magnetics components for hybrid circuits. This paper describes the design and realisation of thick film inductors and transformers using a ferromagnetic ink. A square inductor has been modelled and its magnetic behaviour simulated by using the ANSYS program.

Impedance of long direct massive conductors carrying time‐variable currents is a complex function of time. Its evolution is affected not only by the skin effect but also by the temperature rise. This paper presents a numerical method that allows one to compute the resistance and internal inductance of a non‐ferromagnetic conductor of any cross‐section from values of the total Joule losses and magnetic energy within the conductor, and also illustrates the theoretical analysis based on the field approach on a typical example and discusses the results.

The purpose of this paper is to propose a new propeller-type climbing robot called EJBot for climbing various types of structures that include significant obstacles, besides inspection of industrial vessels made of various materials, including non-ferromagnetic material. The inspection includes capturing images for important spots and measuring the wall thickness.

The design mainly consists of two coaxial upturned propellers mounted on a mobile robot with four standard wheels. A new hybrid actuation system that consists of propeller thrust forces and standard wheel torques is considered as the adhesion system for this climbing robot. This system generates the required adhesion force to support the robot on the climbed surfaces. Dynamic simulation using ADAMS is performed and ensures the success of this idea.

Experimental tests to check the EJBot’s capabilities of climbing different surfaces, such as smooth, rough, flat and cylindrical surfaces like the real vessel, are successfully carried out. In addition, the robot stops accurately on the climbed surface at any desired location for inspection purposes, and it overcomes significant obstacles up to 40 mm.

This proposed climbing robot is needed for petrochemical and liquid gas vessels, where a regular inspection of the welds and the wall thickness is required. The interaction between the human and these vessels is dangerous and not healthy due to the harmful environment inside these vessels.

This robot utilizes propeller thrusts and wheel torques simultaneously to generate adhesion and traction forces. Therefore, a versatile robot able to climb different kinds of structures is obtained.

Magnetic particle flaw detection is one of the longest established and most commonly used methods of non‐destructive testing. It can often be applied in a relatively quick and simple manner. Because of this, it is frequently treated as the “poor relation” in present day non‐destructive test methods and regarded as a method which can be performed by unskilled labour. While this may sometimes be true in semi‐automatic production line testing there are many applications which require considerable knowledge and experience. The use of magnetic particle flaw detection has increased considerably in the past few years. It is now being recognised as essential to supplement visual examination in many areas of in‐service inspection on all types of plant. This article, to be published in four parts, is directed towards maintenance engineers and inspectors who may wish to use the method themselves or would like to have the basic knowledge to ensure that any such tests requested and performed on their behalf, are carried out correctly.