E. Cardelli - Academia.edu (original) (raw)

Papers by E. Cardelli

Research paper thumbnail of Vector Hysteresis Model at Micromagnetic Scale

IEEE Transactions on Magnetics, 2006

In this paper we discuss about the possibility to reproduce the behavior of a magnetic material a... more In this paper we discuss about the possibility to reproduce the behavior of a magnetic material at micromagnetic scale with a phenomenological vector model of hysteresis based on the definition of a vector hysteron. We compare data computed by means of two different static magnetic models. The former is based on the solution of Brown's equation (micromagnetic scale). The latter is a vector generalization of the Classical Scalar Preisach Model (macromagnetic scale). We show that the magnetization versus applied field curves computed by both models are in good agreement, and that the macromagnetic-scale model is able to reproduce the physical behavior of the magnetic materials at micromagnetic scale.

Research paper thumbnail of Classification of eddy current NDT data by probabilistic neural networks

IJCNN'99. International Joint Conference on Neural Networks. Proceedings (Cat. No.99CH36339), 1999

In this paper we discuss the use of the Probabilistic Neural Network (PNN) for the classification... more In this paper we discuss the use of the Probabilistic Neural Network (PNN) for the classification of the defects detected via the Remote Field Eddy Current (RFEC) inspection technique. The neural network is employed in order to associate each defect to one of the predefined classes. Each defect is represented by means of the phase response of the probe system. The reported results show that the proposed artificial neural network allows reliable classification results.

Research paper thumbnail of Numerical comparison between a differential and an integral approach in MHD simulations of electromagnetic railgun plasma armatures

IEEE Transactions on Magnetics, 1997

In this paper an integral approach for the analysis and the numerical simulation of the plasma ar... more In this paper an integral approach for the analysis and the numerical simulation of the plasma armatures operating in rail launchers is tested by comparison with a differential approach. After a brief recall of the main theoretical and numerical aspects of the two approaches, a benchmark problem is presented and analyzed. The comparison between the results obtained confirms the validity and the effectiveness of both methods. Moreover, possible advantages or drawbacks of the computer codes implementing the two approaches are discussed

Research paper thumbnail of Numerical techniques in electromagnetic compatibility-oriented design of rail launchers operating with plasma armatures

IEEE Transactions on Magnetics, 1997

In this paper the electromagnetic interferences radiated from a railgun operating with plasma arm... more In this paper the electromagnetic interferences radiated from a railgun operating with plasma armatures are studied. The level of emission during the initial explosion of the fuse barrel that forms successively the metallic arc is computed by integrating numerically Maxwell's equations in complete form via a suitable numerical code, written in C++ programming language, and based on a three-dimensional finite difference algorithm in the space and in the time domain. The electric and magnetic field during the acceleration of the plasma armature, successive to its formation, are evaluated by means of a quasi-stationary model based on the assumed transient current distribution in the rails and the armature and on a given relation between the current and the position of the armature. The results indicate that both methods can be considered useful tools in the analysis of the electromagnetic environment around rail launchers

Research paper thumbnail of Finite-difference time-domain analysis of the ESD current diffusion in metallic enclosures and of the related radiated electromagnetic fields

IEEE Transactions on Magnetics, 1996

In this paper, the problem of the electromagnetic diffusion of electrostatic discharge (ESD) curr... more In this paper, the problem of the electromagnetic diffusion of electrostatic discharge (ESD) currents, interfering directly on the metallic enclosures of electronic equipments, and of the electromagnetic interferences (EM9 produced, is modeled and computed via a suitable finite-difference timedomain numerical approach. The levels of the radiated fields produced by standard ESD current waveforms in grounded metallic shells are evaluated, and the effects of the different arrangements of the grounding wires of the enclosure on the resulting EM1 levels are discussed.

Research paper thumbnail of Numerical analysis of diffracting perforated shields

IEEE Transactions on Magnetics, 1997

This paper deals with the numerical analysis of the behavior of diffracting perforated shields, a... more This paper deals with the numerical analysis of the behavior of diffracting perforated shields, and in particular of honeycomb structures. The diffracting perforated shield consists of a matrix of metallic waveguides, and its shielding effectiveness depends on the size, the length and the number of waveguides. For the numerical computation a Yee's (1966) finite difference algorithm with Mur's (1981) absorbing boundary conditions is employed. A particular technique allows one to limit the spatial dimension of the simulating grid, suitably taking into account the external field source. The computed results show the effectiveness and the accuracy of the method

Research paper thumbnail of Nonferromagnetic Open Shields at Industrial Frequency Rate

IEEE Transactions on Magnetics, 2000

Research paper thumbnail of Vector Hysteresis Model at Micromagnetic Scale

IEEE Transactions on Magnetics, 2000

In this paper we discuss about the possibility to reproduce the behavior of a magnetic material a... more In this paper we discuss about the possibility to reproduce the behavior of a magnetic material at micromagnetic scale with a phenomenological vector model of hysteresis based on the definition of a vector hysteron. We compare data computed by means of two different static magnetic models. The former is based on the solution of Brown's equation (micromagnetic scale). The latter is a vector generalization of the Classical Scalar Preisach Model (macromagnetic scale). We show that the magnetization versus applied field curves computed by both models are in good agreement, and that the macromagnetic-scale model is able to reproduce the physical behavior of the magnetic materials at micromagnetic scale.

Research paper thumbnail of Analysis methodologies and experimental benchmarks for eddy current testing

IEEE Transactions on Magnetics, 2000

In this paper, we present numerical models and experimental benchmarks for eddy current testing (... more In this paper, we present numerical models and experimental benchmarks for eddy current testing (ECT) applications, developed within the methods and applications of nondestructive electromagnetic diagnostic (MADEND) research project. We compare and validate two different numerical methods for eddy current calculation in the framework of ECT (an integral formulation implemented on a parallel computer system and a discrete formulation based on a geometric approach) by using specifically designed experimental benchmarks and a commercial finite element method based on a differential formulation.

Research paper thumbnail of Epstein frame: how and when it can be really representative about the magnetic behavior of laminated magnetic steels

IEEE Transactions on Magnetics, 2000

In this paper, using suitable three-dimensional finite element method (FEM) approaches, either in... more In this paper, using suitable three-dimensional finite element method (FEM) approaches, either in frequency or in time domain, we will analyze the real magnetic behavior of a commercial Epstein machine, prescribed as standard magnetic measurement system. The analysis of magnetic field and eddy currents explains some facts that can affect the accuracy of Epstein frames as measuring systems for the magnetic characterization of laminated Si-Fe steels. The same FEM approaches shall be applied here to outline and define quantitatively some advantages in accuracy can be obtained using Single Sheet testers instead of Epstein frames.

Research paper thumbnail of The AMDE project: 3D volumetric anomalies reconstruction by eddy current testing

Research paper thumbnail of Analytical evaluation of magnetic energy and stresses in 3-D conductor systems

IEEE Transactions on Magnetics, 1996

Analytical expressions for magnetic energy, selfand mutual coefficients, and forces of three-dime... more Analytical expressions for magnetic energy, selfand mutual coefficients, and forces of three-dimensional ironfree conductors systems constituted by a series of bricks with parallel edges are derived. The expressions presented can be usefully adopted as efficient and time-saving algorithms in integral formulations.

Research paper thumbnail of Vector Hysteresis Model at Micromagnetic Scale

IEEE Transactions on Magnetics, 2006

In this paper we discuss about the possibility to reproduce the behavior of a magnetic material a... more In this paper we discuss about the possibility to reproduce the behavior of a magnetic material at micromagnetic scale with a phenomenological vector model of hysteresis based on the definition of a vector hysteron. We compare data computed by means of two different static magnetic models. The former is based on the solution of Brown's equation (micromagnetic scale). The latter is a vector generalization of the Classical Scalar Preisach Model (macromagnetic scale). We show that the magnetization versus applied field curves computed by both models are in good agreement, and that the macromagnetic-scale model is able to reproduce the physical behavior of the magnetic materials at micromagnetic scale.

Research paper thumbnail of Classification of eddy current NDT data by probabilistic neural networks

IJCNN'99. International Joint Conference on Neural Networks. Proceedings (Cat. No.99CH36339), 1999

In this paper we discuss the use of the Probabilistic Neural Network (PNN) for the classification... more In this paper we discuss the use of the Probabilistic Neural Network (PNN) for the classification of the defects detected via the Remote Field Eddy Current (RFEC) inspection technique. The neural network is employed in order to associate each defect to one of the predefined classes. Each defect is represented by means of the phase response of the probe system. The reported results show that the proposed artificial neural network allows reliable classification results.

Research paper thumbnail of Numerical comparison between a differential and an integral approach in MHD simulations of electromagnetic railgun plasma armatures

IEEE Transactions on Magnetics, 1997

In this paper an integral approach for the analysis and the numerical simulation of the plasma ar... more In this paper an integral approach for the analysis and the numerical simulation of the plasma armatures operating in rail launchers is tested by comparison with a differential approach. After a brief recall of the main theoretical and numerical aspects of the two approaches, a benchmark problem is presented and analyzed. The comparison between the results obtained confirms the validity and the effectiveness of both methods. Moreover, possible advantages or drawbacks of the computer codes implementing the two approaches are discussed

Research paper thumbnail of Numerical techniques in electromagnetic compatibility-oriented design of rail launchers operating with plasma armatures

IEEE Transactions on Magnetics, 1997

In this paper the electromagnetic interferences radiated from a railgun operating with plasma arm... more In this paper the electromagnetic interferences radiated from a railgun operating with plasma armatures are studied. The level of emission during the initial explosion of the fuse barrel that forms successively the metallic arc is computed by integrating numerically Maxwell's equations in complete form via a suitable numerical code, written in C++ programming language, and based on a three-dimensional finite difference algorithm in the space and in the time domain. The electric and magnetic field during the acceleration of the plasma armature, successive to its formation, are evaluated by means of a quasi-stationary model based on the assumed transient current distribution in the rails and the armature and on a given relation between the current and the position of the armature. The results indicate that both methods can be considered useful tools in the analysis of the electromagnetic environment around rail launchers

Research paper thumbnail of Finite-difference time-domain analysis of the ESD current diffusion in metallic enclosures and of the related radiated electromagnetic fields

IEEE Transactions on Magnetics, 1996

In this paper, the problem of the electromagnetic diffusion of electrostatic discharge (ESD) curr... more In this paper, the problem of the electromagnetic diffusion of electrostatic discharge (ESD) currents, interfering directly on the metallic enclosures of electronic equipments, and of the electromagnetic interferences (EM9 produced, is modeled and computed via a suitable finite-difference timedomain numerical approach. The levels of the radiated fields produced by standard ESD current waveforms in grounded metallic shells are evaluated, and the effects of the different arrangements of the grounding wires of the enclosure on the resulting EM1 levels are discussed.

Research paper thumbnail of Numerical analysis of diffracting perforated shields

IEEE Transactions on Magnetics, 1997

This paper deals with the numerical analysis of the behavior of diffracting perforated shields, a... more This paper deals with the numerical analysis of the behavior of diffracting perforated shields, and in particular of honeycomb structures. The diffracting perforated shield consists of a matrix of metallic waveguides, and its shielding effectiveness depends on the size, the length and the number of waveguides. For the numerical computation a Yee's (1966) finite difference algorithm with Mur's (1981) absorbing boundary conditions is employed. A particular technique allows one to limit the spatial dimension of the simulating grid, suitably taking into account the external field source. The computed results show the effectiveness and the accuracy of the method

Research paper thumbnail of Nonferromagnetic Open Shields at Industrial Frequency Rate

IEEE Transactions on Magnetics, 2000

Research paper thumbnail of Vector Hysteresis Model at Micromagnetic Scale

IEEE Transactions on Magnetics, 2000

In this paper we discuss about the possibility to reproduce the behavior of a magnetic material a... more In this paper we discuss about the possibility to reproduce the behavior of a magnetic material at micromagnetic scale with a phenomenological vector model of hysteresis based on the definition of a vector hysteron. We compare data computed by means of two different static magnetic models. The former is based on the solution of Brown's equation (micromagnetic scale). The latter is a vector generalization of the Classical Scalar Preisach Model (macromagnetic scale). We show that the magnetization versus applied field curves computed by both models are in good agreement, and that the macromagnetic-scale model is able to reproduce the physical behavior of the magnetic materials at micromagnetic scale.

Research paper thumbnail of Analysis methodologies and experimental benchmarks for eddy current testing

IEEE Transactions on Magnetics, 2000

In this paper, we present numerical models and experimental benchmarks for eddy current testing (... more In this paper, we present numerical models and experimental benchmarks for eddy current testing (ECT) applications, developed within the methods and applications of nondestructive electromagnetic diagnostic (MADEND) research project. We compare and validate two different numerical methods for eddy current calculation in the framework of ECT (an integral formulation implemented on a parallel computer system and a discrete formulation based on a geometric approach) by using specifically designed experimental benchmarks and a commercial finite element method based on a differential formulation.

Research paper thumbnail of Epstein frame: how and when it can be really representative about the magnetic behavior of laminated magnetic steels

IEEE Transactions on Magnetics, 2000

In this paper, using suitable three-dimensional finite element method (FEM) approaches, either in... more In this paper, using suitable three-dimensional finite element method (FEM) approaches, either in frequency or in time domain, we will analyze the real magnetic behavior of a commercial Epstein machine, prescribed as standard magnetic measurement system. The analysis of magnetic field and eddy currents explains some facts that can affect the accuracy of Epstein frames as measuring systems for the magnetic characterization of laminated Si-Fe steels. The same FEM approaches shall be applied here to outline and define quantitatively some advantages in accuracy can be obtained using Single Sheet testers instead of Epstein frames.

Research paper thumbnail of The AMDE project: 3D volumetric anomalies reconstruction by eddy current testing

Research paper thumbnail of Analytical evaluation of magnetic energy and stresses in 3-D conductor systems

IEEE Transactions on Magnetics, 1996

Analytical expressions for magnetic energy, selfand mutual coefficients, and forces of three-dime... more Analytical expressions for magnetic energy, selfand mutual coefficients, and forces of three-dimensional ironfree conductors systems constituted by a series of bricks with parallel edges are derived. The expressions presented can be usefully adopted as efficient and time-saving algorithms in integral formulations.