Coupled Field-Circuit Finite Element Models of a Cold Crucible Furnace in its Environment (original) (raw)

DESIGN AND IMPLEMENTATION OF AN INDUCTION FURNACE

The design of a certain induction furnace for a certain application depends mostly on empirical formulas and experience. The purpose of this work is to use the Finite Element Method (FEM) approach to perform an electromagnetic-thermal coupled analysis for a suggested coil with certain billet and studying its performance during the heating period. This will lead to the ability of expecting the required coil current and its frequency, to heat certain part of a certain billet to a certain temperature at the predetermined time. Then, the simulation results can be used to build the coil and leads to design the power supply for the induction furnace. The practical measurement of the designed system agrees with that of the theoretical design results. Hence, this approach assists to reduce the design cost, time and efforts for any other required induction furnace.

A FEM/BEM for axisymmetric electromagnetic and thermal modelling of induction furnaces

… journal for numerical …, 2007

In this paper, we propose a numerical method to solve a mathematical model for axisymmetric induction furnaces used for melting materials like metals or silicon. A finite/boundary element method (FEM/BEM) is introduced to solve the eddy current problem giving the electromagnetic field. In order to solve the non-linear heat transfer problem involving change of state, we use an enthalpy formulation and propose an iterative algorithm to solve the corresponding finite element approximation. Numerical results for an industrial induction heating system are presented.

Field-Data-Based Modeling of Medium-Frequency Induction Melting Furnaces for Power Quality Studies

IEEE Transactions on Industry Applications, 2012

In this paper, the coreless medium-frequency induction melting furnace (IMF) system is represented by alternative field-data-based models, developed specifically for power quality studies. The IMF operation has been represented by a variable series RL circuit, to model the fundamental components of electrical quantities, and a shunt-connected current source, to model the generated harmonics and interharmonics over a typical melting cycle. Both the sinusoidal coding method applied to the major harmonics and interharmonics in the supply line currents obtained from field measurements and the raw data have been used in the developed models. It has been shown that the sinusoidal coding method can be used to satisfactorily represent the operation of the IMF system as seen from the supply terminals, with a minimum data storage requirement, and can be used to construct efficient IMF databases for power quality studies. The power quality problems of the IMF system, particularly the problematic time-varying interharmonic voltage distortion, and the interaction of those time-varying interharmonic currents with the passive shunt filter installations connected to the same bus have been investigated in detail, using the developed models.

Numerical studies of the melting process in the induction furnace with cold crucible

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 2008

Purpose-Aims to present recent activities in numerical modeling of cold crucible melting process. Design/methodology/approach-3D numerical analysis was used for electromagnetic problem and 3D large eddy simulation (LES) method was applied for fluid flow modeling. Findings-The comparative modeling shows, that higher H/D ratio of the melt is more efficient when total power consumption is considered, but this advantage is held back by higher heat losses through the crucible walls. Also, calculations reveal that lower frequencies, which are energetically less effective, provide better mixing of the melt. Originality/value-3D electromagnetic model, which allows to take into account non-symmetrical distribution of Joule heat sources, together with transient LES fluid flow simulation gives the opportunity of accurate prediction of temperature distribution in the melt.

Application of equivalent thermal circuits for calculation of thermal processes of induction cruel furnaces with a capacity of up to 1000 kg

E3S Web of Conferences, 2021

The article describes new approaches to calculating the thermal regimes of induction crucible furnaces, as well as methods for calculating them using converted thermal circuits. The principles of constructing thermal models of structural parts and molten metal of induction crucible furnaces based on converted ETS and their use for the development of optimal systems for automatic control of the metal melting process are considered. The methodology for the development of ETS and the compilation of heat balance equations for induction crucible furnaces with a capacity of up to 1000 kg is presented..

The mathematical model of induction heating of ferromagnetic pipes

IEEE Transactions on Magnetics, 1989

In this paper a mathematical model of coupled heat transfer and electromagnetic phenomena in induction heaters of ferromagnetic, steel pipes has been described. The model takes into account the nonlinearity of all coefficients, the characteristics of the supply source, and the thermal influence of the lining. A method of partial decoupling of fields has been proposed. Experimental verification of the computed results has also been presented.

Simulation-Driven Design and Optimization of a New Two-Coil Crucible Induction Furnace Using the Altair FLUX3D® Software

Innovations, 2019

A new two-coil crucible induction furnace with a lateral coil connected to the one-phase electric power supply and a bottom coil connected to a capacitor bank with an appropriate value of the capacity is able to realize a desired balance between the induction heating of the lateral face and of the bottom face of the furnace bath. The evaluation of the optimum value of the capacity, which corresponds to the same mean value of the induced power density on the respective faces, represents an example of simulation-driven optimal design. Finite element models are used to study many variants of the new furnace related the number of turns of the two coils and related the diameter of the furnace bath for imposed bath volume.

Shielding of EM fields in induction heating and melting installations

The purpose of the work is to evaluate the EMF levels in the surroundings of particular induction heating installations used for melting metals and some methods for mitigating them. The data from measurements in a metal foundry will be presented and discussed with reference to the limits for occupational environment. In some cases the measured levels overcome the ICNIRP limits. For these cases a deep study to mitigate the exposure levels of the workers has been done by means of numerical simulations. Ad hoc numerical method is proposed and discussed. Some solutions for decreasing the levels of electromagnetic fields (in particular magnetic flux density in the case of induction heating devices) are proposed. These solutions have been tested in the foundry and the field levels after shielding have been compared with the model prediction.

Numerical Analysis of Metals Under The Influence of Electromagnetic Field at Different Current Values

İmalat Teknolojileri ve Uygulamaları

The primary factors of the widespread use of induction melting furnaces are uniform metal and heat distribution due to its mixing features, low alloy losses, excellent temperature and composition control, versatility in processing different materials, the ability to quickly start the process from a cold state when needed, and the absence of air pollution problems. In induction heating, not all sides of the part to be heated receive an equal amount of heat. Only if the part to be heated is of the type that conducts heat very well can all sides of the part be heated close to each other. Induction heating produces high heat on the surface, less on the inner parts, and least on the center of the material. This heating varies depending on the frequency of the current source and the penetration depth. In this study, a model was created in ANSYS numerical analysis program by taking the current, which is one of the electromagnetic and thermal parameters affecting the temperature distributio...