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Purpose: The purpose of this paper is to present the main experimental results obtained on the first prototype of an innovative induction heating system. MAGNHEAT was a LIFE project, funded by EU Commission, proposed to demonstrate the possibility of industrial application of a new technology for the induction heating of aluminum billets before extrusion. This technology uses permanent magnet heaters (PMHs), which constitute a high efficiency solution for the heating of high conductive metals. Design/methodology/approach: The paper briefly describes the main steps of the project: the design of the PMH, the realization and installation of the demonstrator on an extrusion production line of Pandolfo Alluminio SpA and, mostly, the performance of the system. Findings: The main results achieved during the preliminary tests on an industrial line have been summarized by evaluating some key performance indicators, as reported in the paper. Originality/value: The new technology allows a significant reduction of the energy consumption and guarantees the same performance of a classical induction heater. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the possibility of controlling the electromagnetic stirrer (EMS) is fundamental in a continuous casting line to achieve the desired properties of homogeneity and mechanical strength in the solidified cast. Design/methodology/approach: Coupled electromagnetic (EM) and fluid dynamic (FD) simulations allow to predict the mixing effect on molten metal, in terms of velocity amplitude and shape of the flow. This paper describes the numerical results of EMS effect within a cylindrical crucible, surrounded by a solenoidal inductor, filled with a low melting temperature alloy, i.e. GalInStan. Findings: Induced forces and resulting velocity distribution of the flow of the liquid metal have been calculated depending on varying amplitude and frequency of the supplied current. As expected, at a given amplitude of the current supply, the velocity distribution shows a maximum at a certain frequency while the intensity of electrodynamic forces monotonically increase as the frequency increases Originality/value: The paper deals with simply models and experiments applied to coupled EM and FD problem, to assess the applied methodology. [ABSTRACT FROM AUTHOR]

Purpose: An inductor for the uniform heating of the extremity of a ferromagnetic steel tube for stress relieving is considered. The main goal of the study is to investigate the possibility to achieve a reasonable design of the inductor when dealing with many design variables. Design/methodology/approach: Genetic optimization algorithms are used for this purpose, demonstrating the applicability of these techniques to the design of induction heating inductors. Genetic algorithms provide to the designer several optimal solutions belonging to Pareto Front, and this way they allow choosing the solution that better fits the technological requirements. In any case, the designer has to adapt the chosen solution to fit in with the real possibilities in industrial application. Findings: The study demonstrates that automatic optimization methods may help the designer of the induction heating system to solve complex problems with very conflicting technological requirements. Originality/value: In the paper, a problem with a high number of design variables is solved. Moreover, the goals of the optimization process are strongly conflicting, and the proposed problem is a challenging one. [ABSTRACT FROM AUTHOR]

Purpose In electrochemotherapy, flexible electrodes, composed by an array of needles, are applied to human tissues to treat large surface tumors. The positioning of the needles in the tissue depends on the surface curvature. The parallel needle case is preferred, as their relative inclinations strongly affect the actual distribution of electric field. Nevertheless, in some case, small inclinations are unavoidable. The purpose of this paper is to study the electric field distribution for non-parallel needles.Design/methodology/approach The effect of electrode position is evaluated systematically by means of numerical models and experiments on phantoms for two different angles (5° and 30°) and compared with the case of parallel needles. Potato model was used as phantom, as this tissue becomes dark after few hours from electroporation. The electroporation degree was gauged from the color changings on the potatoes.Findings The distribution of electric field in different needle configuration is found by means of finite element analysis (FEA) and experiments on potatoes. The electric field level of inclined needles was compared with parallel needle case. In particular, the electric field distribution in the case of inclined needles could be very different with respect to the one in the case of parallel needles. The degree of enhancement for different inclinations is visualized by potato color intensity. The FEA suggested that the needle parallelism has to be maintained as possible as if the tips are closer to each other, the electric field intensity could be different with respect to the one in the case of parallel needles.Originality/value This paper analyzes the effect of inclined electrodes considering also the non-linearity of tissues. [ABSTRACT FROM AUTHOR]

Purpose This paper aims to present the optimal design of an inductor used to heat a magnetic nanoparticle fluid injected in a cell culture inside a Petri dish.Design/methodology/approach The inductor design is driven by means of a multi-objective optimization algorithm that generalizes the migration-non-dominated sorting genetic algorithm (NSGA); it is called self-adapting migration-NSGA.Findings The optimized device is able to synthesize a uniform magnetic field in a nanoparticle fluid, substantially helping its heating capability. The ultimate scope is to assist the cancer therapy based on magnetic fluid hyperthermia (MFH).Originality/value The optimal design of an inductor for MFH applications has been carried out by applying an improved version of migration-based NSGA-II algorithm including automatic stop and a self-adapting concept. The modified optimization algorithm is suitable to find better optimal solutions with respect to a standard version of NSGA-II. [ABSTRACT FROM AUTHOR]

Purpose – In the paper, a single-objective optimization problem characterized by high-frequency field analysis is investigated: the optimal design of a two-port microwave (MW) oven, taking into account the possibility of two independently controlled sources, with the aim of improving the efficiency is considered as the case study. The paper aims to discuss these issues. Design/methodology/approach – A high-frequency field analysis has been coupled to a robust evolutionary-computing algorithm in order to create an appropriate procedure for the optimal design of a MW oven based on a cascade optimization: in the first step the optimized geometry has been identified, while in the second step the optimized electrical supply values have been synthesized. In particular, the direct problem has been faced by means of a 3D-FEM approach in order to obtain realistic results; the inverse problem has been faced by means of a derivative-free robust algorithm based on evolutionary strategy in order to get a fast convergence of the solution. Findings – A new design procedure for high efficiency MW ovens for household application by means of the proposed numerical approach. Practical implications – These results allow industrial designers to improve this kind of devices. Originality/value – The original contribution of the paper is the systematic approach to the optimal design of a MW oven with multiple feeding, based on the link between an algorithm of evolutionary strategy optimization algorithm and a finite-element solver. [ABSTRACT FROM AUTHOR]

HES conference is a meeting point for different cultures and expertise. The exploitation of multi-objective optimization techniques and evolutionary computing algorithms help the solution of the inverse problem. First, a short focus on a few hot topics in our community, such as multi-physics modelling and optimal synthesis methods, is more oriented to scientific aspects. [Extracted from the article]