International Journal of Applied Electromagnetics and Mechanics - Volume 53, issue S1

Article Type: Other

DOI: 10.3233/JAE-162233

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S1-S2, 2017

Authors: Marioni, L. | Alves, J. | Bay, F. | Hachem, E.

Article Type: Research Article

Abstract: Electromagnetic stirring (EMS) is widely used to increase the efficiency in continuous casting process of steel. In particular, in-mould applications (M-EMS) allow decreasing the free surface fluctuation, controlling the velocity field and decreasing the turbulence of the flow. Since laboratory-scale tests are not fully representative of the process and industrial measurements are both expensive and difficult to carry out, numerical simulation is a strong tool to study and optimize these electromagnetic applications in steel industry. These simulations cannot fully model the process of its multiphysical nature and the simulation of all the phenomena involved would lead to huge computational costs, …which is one of the main limits in the current situation. For this reason, this work aims at starting searching a coupling algorithm which could guarantee both computational efficiency and accuracy of the final results. Show more

Keywords: Continuous casting, electromagnetic stirring, mesh adaptation, finite elements

DOI: 10.3233/JAE-162245

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S3-S10, 2017

Authors: Shoihet, A. | Frechter, Y. | Berdichevsky, V. | Shvartsas, M. | Rabinovici, R.

Article Type: Research Article

Abstract: Levitation melting is one of the unique techniques in containerless melting experiments and solidification of materials for processing under high magnetic fields. In recent years this technique has spread to other research areas of metallurgy and it is currently used in applications like alloy preparation, metal purification and grain refinement. Usually, levitation melting is achieved by using coaxial two-section coils. The bottom and the upper sections carry currents in opposite directions. Different apparatus coil configurations and electrical parameters, like current frequency and amplitude, have a direct effect on the free surface shape of the molten charge. It is crucial …to know the final molten metal shape, as a prediction tool of levitation melting success, during design procedure. By means of developed iterative model, the equilibrium shape of levitated molten metal is found. This model takes into considerations a balance of hydrostatic, surface tension and magnetic pressures at the metal interface. The predicted shapes of the metal droplet as well as its position inside the inductor are correlate with that of the experimental data. Show more

Keywords: Electromagnetic levitation, shape control, induced eddy currents, levitation melting

DOI: 10.3233/JAE-162234

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S11-S19, 2017

Authors: Lundström, Fredrik | Frogner, Kenneth | Wiberg, Oscar | Cedell, Tord | Andersson, Mats

Article Type: Research Article

Abstract: Carbon fiber reinforced plastics, CFRP, are attractive materials not only because of their strength and stiffness but also because of their electrical conductivity and high thermal conductivity and diffusivity. One application where induction heating of CFRP is particularly interesting is tools for fast thermal cycling, beneficial in many industrial processes, for example in composite manufacturing. The electrical properties make it possible to heat with induction and the high thermal conductivity allows fast heat equalization. In order to control inducting heating of CFRP it is desirable to know the electrical and thermal properties of the composite. This work presents developed experimental …methods that are used in an investigation of how the thermal and electrical properties of CFRP structures are affected by the fiber properties and composite structure. The experiments and simulations show that fiber type and fiber volume fraction are of great importance for the electrical and thermal properties. The relation between fiber volume fraction and equivalent resistivity is nonlinear and the experiments indicate that a fiber volume fraction exceeding 60% is necessary to achieve a fairly isotropic resistivity and uniform induction heating pattern. Show more

Keywords: Carbon fiber composites, CFRP, induction heating, uniform heating, isotropy

DOI: 10.3233/JAE-162235

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S21-S30, 2017

Authors: Pavlovs, Sergejs | Jakovics, Andris | Baake, Egbert | Sushkovs, Vadims

Article Type: Research Article

Abstract: The paper presents transient distributions of physical fields, computed with LES (Large Eddy Simulation ), for turbulent bubbles flow through electrically conductive liquid in rectangle bubble reactor (RBR ) or cylindrical bubble reactor (CBR ), which are placed in external uniform horizontal or vertical magnetic field. Experimentally verified (without magnetic field) Euler-Euler approach, realized with ANSYS Fluent Magnetohydrodynamic (MHD ) module , is used for multiphase flow, when continuous phase is electrically conductive liquid (water-like liquid or Wood -metal) and dispersed phase is gas (air or nitrogen) bubbles.

Keywords: Numerical simulation, bubble reactor, multiphase MHD-flow, Euler-Euler approach, LES, uniform magnetic field

DOI: 10.3233/JAE-162236

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S31-S41, 2017

Authors: Beckstein, Pascal | Galindo, Vladimir | Gerbeth, Gunter

Article Type: Research Article

Abstract: With the Ribbon Growth on Substrate (RGS) technology, a new crystallization technique is available that allows controlled high crystallization rate production of silicon wafers and advanced metal-silicide alloys. Compared to other casting methods, such as e.g. directional solidification, the RGS process allows better crystallization control, high volume manufacturing and high material yield due to its continuous, substrate-driven design. Insights from modelling the characteristic melt flow in the casting frame are very desirable. To address this demand, we are developing a new numerical tool based on OpenFOAM [1] which can be utilized to simulate the free-surface dynamics of the melt …flow under the influence of alternating electromagnetic fields. The underlying multi-physical model involves three-dimensional hydrodynamic and magnetodynamic effects and their interaction. Show more

Keywords: Ribbon Growth on Substrate, numerical simulation, coupled multi-physics, free-surface flow, eddy-currents

DOI: 10.3233/JAE-162237

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S43-S51, 2017

Authors: Ruggiero, M. Rosaria | Geninatti Crich, Simonetta | Sieni, Elisabetta | Sgarbossa, Paolo | Cavallari, E. | Stefania, Rachele | Dughiero, Fabrizio | Aime, Silvio

Article Type: Research Article

Abstract: Recently, nanoscale stimuli-responsive devices have received much attention thanks to their potential to limit the cytotoxic effect of the therapeutic treatment at the diseased tissue. Among different physical triggers, large alternating magnetic fields enable the conversion of magnetic energy into heat by using magnetic nanoparticles that generate localized hyperthermia, named Magneto Fluid Hyperthermia (MFH). This methodology can be exploited for cancer therapy or/and thermally activated drug release. The small size iron oxide nanoparticles (Fe-NPs), such as SPIO (small iron oxide particles) and USPIO (ultra-small iron oxide particles), currently used for this application have many limitations due to their 1) …high intratumor concentration needed due to the low heating power 2) short particle blood-half-life, 3) non-specific distribution, 4) low internalization efficiency. For these reasons many efforts are necessary to make magneto fluid particle hyperthermia (MFH) a competitive tumor therapy for clinical applications. New iron oxide nanoparticles, coated with oleate, with a diameter of 5-18 nm, have been prepared by co-precipitation and incorporated into PLGA-NPs (PLGA=Poly(lactic-co-glycolic acid) in order to improve their biocompatibility and ``in vivo '' stability. Moreover, PLGA-NPs have been loaded with both NPs-Fe and antitumor drugs (Paclitaxel, PTX), an anticancer hydrophobic drug used in the treatment of ovarian and breast cancer, to perform MFH triggered drug release. The PTX and Fe-NPs loaded nanoparticles may be considered as an effective anticancer drug delivery system for Imaging-guided hyperthermic treatment of tumors. Show more

Keywords: Magnetic fluid hyperthermia, iron oxide particles, poly lactic and glycolic acid, nuclear magnetic resonance, paclitaxel

DOI: 10.3233/JAE-162246

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S53-S60, 2017

Authors: Spitans, Sergejs | Baake, Egbert | Jakovics, Andris | Franz, Henrik

Article Type: Research Article

Abstract: In this paper, a drip- and leakage-free approach for electromagnetic (EM) levitation melting of metallic samples in horizontal and orthogonal two-frequency fields is studied further. Numerical simulation is used to design an experimental furnace for a stable levitation melting of aluminum samples with increased weight. The scale-up of the method is validated by experiments with aluminum (Al) samples up to 0.5 kg.

Keywords: Electromagnetic levitation, liquid metal, free surface, numerical simulation

DOI: 10.3233/JAE-162238

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S61-S66, 2017

Authors: Terzijska, Džulia | Lüdtke, Ulrich

Article Type: Research Article

Abstract: Lorentz force velocimetry (LFV) [1] is a contactless measurement technique, which uses the principle of induction to analyze physical properties of moving and electrically conducting media. We report a systematic numerical optimization procedure with finite element (FEM) simulation to improve the measurement quality of LFV for weakly conducting media. The force can be increased by optimizing the primary magnetic field created by a magnet system. We use magnetic dipoles as field sources. Analytic and numerical studies of the influence of single magnetic dipoles on the conducting medium have been investigated [2-4]. The optimization of different dipole configurations with a high …number of dipoles is new and presents the next step in the development of Lorentz force flowmeters for weakly conducting fluids for industrial application. We study and optimize the orientation of dipoles with the FEM software PROMETHEUS and develop an optimization method. The resulting optimized dipoles exhibit characteristic orientations, which are point symmetric with respect to the center of the geometric setup so that the magnitudes of the vector fields wind themselves like a spiral around the pipe. Show more

Keywords: Gradient-ascent, Lorentz force, low magnetic Reynolds number, magnetic dipoles, optimization

DOI: 10.3233/JAE-162239

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S67-S78, 2017

Authors: Schubotz, S. | Nacke, B.

Article Type: Research Article

Abstract: In high performance induction heating systems, the coil often has a short lifetime as a result of high power density generated in some areas. The cause of life reduction is often because the cooling effect of the coolant is not sufficient or the heat is not dissipated adequately. This is usually due to a poor heat transfer between the cooling water and the coil. The sizing of the cooling system and the coil have a high impact on the heat transfer and therefore also on service life. Generally, the system parameters affected by this dimensioning are the cooling water temperature, …cooling water flow (velocity) and pressure. In this paper, a method is presented which allows a research of the influences by these different parameters on the heat transfer coefficient. For this purpose, a water-cooled, cylindrical copper part is heated by induction and the heat transfer to the coolant is examined. Considering that, a concept has been developed and analyzed by means of a 2D model. This is followed by the implementation of the model using an experimental setup, where an individual adjustment of the three cooling parameters has been realized and also its impacts on the heat transfer coefficient. Show more

Keywords: Induction heating, convective heat transfer coefficient, lifetime of coils

DOI: 10.3233/JAE-162240

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. S1, pp. S79-S88, 2017