Vasile-Daniel DAN - Academia.edu (original) (raw)

Uploads

Conference Presentations by Vasile-Daniel DAN

IEEE, 2011

The magnetization dynamics is described by a mathematical model that represents a time dependent ... more The magnetization dynamics is described by a mathematical model that represents a time dependent nonlinear differential equation, known as the Landau-Lifshitz-Gilbert equation (LLG). This paper investigates several numerical methods for solving different LLG equation types. The results are compared with the analytical solution as well as with some literature versions.

IEEE, 2013

The paper analyses two measurement procedures of magnetic field in electromagnets for particle ac... more The paper analyses two measurement procedures of magnetic field in electromagnets for particle accelerators. In these devices, it is of interest the magnetic field distribution, in the neighborhood of their axis. This distribution is not measured directly, but by using the measurements of magnetic flux density, in a finite number of points selected by users. Based on these measurements, an analytical method is used to determine field variation in the circular aperture of electromagnet, and to extract the coefficients of their multipole (harmonic) expansion.
Experimental characterizations, by using measurements along radius and along aperture periphery are analyzed and compared. It is proven that the circular measurements are more robust, because the radial ones leads to a weak conditioned problem, which is not well-posed, in the sense of Hadamard.

IEEE, 2015

This paper presents the analysis, characterization and optimization of a dipole magnet prototype ... more This paper presents the analysis, characterization and optimization of a dipole magnet prototype for The High-Energy Storage Ring (HESR) of the Facility for Antiproton and Ion Research (FAIR). Magnet design and construction, according to beneficiary requirements, are presented. A 2D magnetic modeling optimization of the magnetic pole shape is required in order to obtain a good homogeneity of the magnetic field in the center of the magnet. The numeric modeling is validated by magnetic measurements made on the considered prototype, using a measurement system with Hall Probe.

IEEE, 2017

This paper proposes analytical and numerical models for the measurement process of Eddy-Current (... more This paper proposes analytical and numerical models for the measurement process of Eddy-Current (EC) nondestructive testing. EC inspection represents an essential method for the electromagnetic nondestructive evaluation (NDE) of cracks in conductive materials, with its main applications being found in the examination of aircraft, particle accelerators, and other engineering constructions. The method is based on the detection of the magnetic field produced by eddy currents induced in the specimen being tested. The presence of a crack disturbs the flow of the eddy currents, thus producing a magnetic field perturbation dependent on the position and shape of the defect itself. Variations in the electrical conductivity and magnetic permeability of the test object material, and the presence of defects in the object causes a change in eddy current and a corresponding change in phase and amplitude that can be detected by measuring the impedance changes in the magnetic field generating coil, which is a telltale sign of the presence of defects. The nature of the method is complex and there is therefore a need for deeper understanding that may be gained from mathematical models. Such models can have several objectives as for example procedure and equipment optimization or understanding of the method capability and reliability.

IEEE, 2019

The paper analyses a measurement procedure of the magnetic field in the aperture of hexapolar mag... more The paper analyses a measurement procedure of the magnetic field in the aperture of hexapolar magnets for particle accelerators. In this respect, a standard program for magnetic measurements has been applied for these types of magnets. The purpose of this paper is to improve, develop and verify (using the experimental data of another device) the procedure outlined in [1].

IEEE, 2017

The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage sys... more The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage system (FESS) is the result of computationally intensive task. Magnetic bearing are increasingly being used for large variety of applications. The paper presents the verification process of force vs. displacement for a PMB conducted with analytical computation and compared with a finite element analysis (FEA) which was made with Comsol Multiphysics 3.5a simulation software for various physics and engineering applications. Also there is shown the 3D CAD design of the PMB and the relative error between analytical and numerical results.

Papers by Vasile-Daniel DAN

2017 10th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2017

The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage sys... more The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage system (FESS) is the result of computationally intensive task. Magnetic bearing are increasingly being used for large variety of applications. The paper presents the verification process of force vs. displacement for a PMB conducted with analytical computation and compared with a finite element analysis (FEA) which was made with Comsol Multiphysics 3.5a simulation software for various physics and engineering applications. Also there is shown the 3D CAD design of the PMB and the relative error between analytical and numerical results.

2017 10th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2017

This paper proposes analytical and numerical models for the measurement process of Eddy-Current (... more This paper proposes analytical and numerical models for the measurement process of Eddy-Current (EC) non-destructive testing. EC inspection represents an essential method for the electromagnetic nondestructive evaluation (NDE) of cracks in conductive materials, with its main applications being found in the examination of aircraft, particle accelerators, and other engineering constructions. The method is based on the detection of the magnetic field produced by eddy currents induced in the specimen being tested. The presence of a crack disturbs the flow of the eddy currents, thus producing a magnetic field perturbation dependent on the position and shape of the defect itself. Variations in the electrical conductivity and magnetic permeability of the test object material, and the presence of defects in the object causes a change in eddy current and a corresponding change in phase and amplitude that can be detected by measuring the impedance changes in the magnetic field generating coil, which is a telltale sign of the presence of defects. The nature of the method is complex and there is therefore a need for deeper understanding that may be gained from mathematical models. Such models can have several objectives as for example procedure and equipment optimization or understanding of the method capability and reliability.

Physica Scripta, 2015

The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Res... more The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Research (FAIR) international project [1], which will be set up in Darmstadt in the next years, contains, among other magnets, several corrector magnets used for vertical and horizontal beam deviation. A prototype of a 2mrad vertical steerer magnet was designed by National Institute for R&D in Electrical Engineering (ICPE-CA) Romania in close cooperation with Forschungszentrum Julich Germany [2] and then manufactured and tested by ICPE-CA [3], Romanian Institute for Electrical Engineering—Advanced Research. Magnetic field measurements using a 3D Hall probe were performed. Measured data and their analysis are presented. The system used for Hall probe positioning and data acquisition is also described.

2015 9th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2015

This paper presents the analysis, characterization and optimization of a dipole magnet prototype ... more This paper presents the analysis, characterization and optimization of a dipole magnet prototype for The High-Energy Storage Ring (HESR) of the Facility for Antiproton and Ion Research (FAIR). Magnet design and construction, according to beneficiary requirements, are presented. A 2D magnetic modeling optimization of the magnetic pole shape is required in order to obtain a good homogeneity of the magnetic field in the center of the magnet. The numeric modeling is validated by magnetic measurements made on the considered prototype, using a measurement system with Hall Probe.

International Journal for Multiscale Computational Engineering, 2015

Accurate data about electric field on the metal-insulator interface are essential for a series of... more Accurate data about electric field on the metal-insulator interface are essential for a series of phenomena, such as electric breakdown, corona discharges, or electron emission. As the size of the structures used in electronics industry goes toward nanoscopic scale, the sharp edge electrostatic effect in these structures becomes more predominant and a correct estimation of the electric field intensity value implies using combined numerical and analytical methods. The implications of the theoretical obtained results are analyzed by considering experimental data.

Advanced Topics in Electrical …, 2011

The magnetization dynamics is described by a mathematical model that represents a time dependent ... more The magnetization dynamics is described by a mathematical model that represents a time dependent nonlinear differential equation, known as the Landau—Lifshitz—Gilbert equation (LLG). This paper investigates several numerical methods for solving different ...

Journal for Multiscale Computational Engineering / Begell House, Inc., 2015

Accurate data about electric field on the metal-insulator interface are essential for a series of... more Accurate data about electric field on the metal-insulator interface are essential for a series of phenomena, such as electric breakdown, corona discharges, or electron emission. As the size of the structures used in electronics industry goes toward nanoscopic scale, the sharp edge electrostatic effect in these structures becomes more predominant and a correct estimation of the electric field intensity value implies using combined numerical and analytical methods. The implications of the theoretical obtained results are analyzed by considering experimental data.

Physica Scripta, 2015

The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Res... more The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Research (FAIR) international project [1], which will be set up in Darmstadt in the next years, contains, among other magnets, several corrector magnets used for vertical and horizontal beam
deviation. A prototype of a 2mrad vertical steerer magnet was designed by National Institute for R&D in Electrical Engineering (ICPE-CA) Romania in close cooperation with Forschungszentrum Jülich Germany [2] and then manufactured and tested by ICPE-CA [3],
Romanian Institute for Electrical Engineering—Advanced Research. Magnetic field measurements using a 3D Hall probe were performed. Measured data and their analysis are presented. The system used for Hall probe positioning and data acquisition is also described.

IEEE, 2011

The magnetization dynamics is described by a mathematical model that represents a time dependent ... more The magnetization dynamics is described by a mathematical model that represents a time dependent nonlinear differential equation, known as the Landau-Lifshitz-Gilbert equation (LLG). This paper investigates several numerical methods for solving different LLG equation types. The results are compared with the analytical solution as well as with some literature versions.

IEEE, 2013

The paper analyses two measurement procedures of magnetic field in electromagnets for particle ac... more The paper analyses two measurement procedures of magnetic field in electromagnets for particle accelerators. In these devices, it is of interest the magnetic field distribution, in the neighborhood of their axis. This distribution is not measured directly, but by using the measurements of magnetic flux density, in a finite number of points selected by users. Based on these measurements, an analytical method is used to determine field variation in the circular aperture of electromagnet, and to extract the coefficients of their multipole (harmonic) expansion.
Experimental characterizations, by using measurements along radius and along aperture periphery are analyzed and compared. It is proven that the circular measurements are more robust, because the radial ones leads to a weak conditioned problem, which is not well-posed, in the sense of Hadamard.

IEEE, 2015

This paper presents the analysis, characterization and optimization of a dipole magnet prototype ... more This paper presents the analysis, characterization and optimization of a dipole magnet prototype for The High-Energy Storage Ring (HESR) of the Facility for Antiproton and Ion Research (FAIR). Magnet design and construction, according to beneficiary requirements, are presented. A 2D magnetic modeling optimization of the magnetic pole shape is required in order to obtain a good homogeneity of the magnetic field in the center of the magnet. The numeric modeling is validated by magnetic measurements made on the considered prototype, using a measurement system with Hall Probe.

IEEE, 2017

This paper proposes analytical and numerical models for the measurement process of Eddy-Current (... more This paper proposes analytical and numerical models for the measurement process of Eddy-Current (EC) nondestructive testing. EC inspection represents an essential method for the electromagnetic nondestructive evaluation (NDE) of cracks in conductive materials, with its main applications being found in the examination of aircraft, particle accelerators, and other engineering constructions. The method is based on the detection of the magnetic field produced by eddy currents induced in the specimen being tested. The presence of a crack disturbs the flow of the eddy currents, thus producing a magnetic field perturbation dependent on the position and shape of the defect itself. Variations in the electrical conductivity and magnetic permeability of the test object material, and the presence of defects in the object causes a change in eddy current and a corresponding change in phase and amplitude that can be detected by measuring the impedance changes in the magnetic field generating coil, which is a telltale sign of the presence of defects. The nature of the method is complex and there is therefore a need for deeper understanding that may be gained from mathematical models. Such models can have several objectives as for example procedure and equipment optimization or understanding of the method capability and reliability.

IEEE, 2019

The paper analyses a measurement procedure of the magnetic field in the aperture of hexapolar mag... more The paper analyses a measurement procedure of the magnetic field in the aperture of hexapolar magnets for particle accelerators. In this respect, a standard program for magnetic measurements has been applied for these types of magnets. The purpose of this paper is to improve, develop and verify (using the experimental data of another device) the procedure outlined in [1].

IEEE, 2017

The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage sys... more The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage system (FESS) is the result of computationally intensive task. Magnetic bearing are increasingly being used for large variety of applications. The paper presents the verification process of force vs. displacement for a PMB conducted with analytical computation and compared with a finite element analysis (FEA) which was made with Comsol Multiphysics 3.5a simulation software for various physics and engineering applications. Also there is shown the 3D CAD design of the PMB and the relative error between analytical and numerical results.

2017 10th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2017

The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage sys... more The design stage optimization of passive magnetic bearing (PMB) for a flywheel energy storage system (FESS) is the result of computationally intensive task. Magnetic bearing are increasingly being used for large variety of applications. The paper presents the verification process of force vs. displacement for a PMB conducted with analytical computation and compared with a finite element analysis (FEA) which was made with Comsol Multiphysics 3.5a simulation software for various physics and engineering applications. Also there is shown the 3D CAD design of the PMB and the relative error between analytical and numerical results.

2017 10th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2017

This paper proposes analytical and numerical models for the measurement process of Eddy-Current (... more This paper proposes analytical and numerical models for the measurement process of Eddy-Current (EC) non-destructive testing. EC inspection represents an essential method for the electromagnetic nondestructive evaluation (NDE) of cracks in conductive materials, with its main applications being found in the examination of aircraft, particle accelerators, and other engineering constructions. The method is based on the detection of the magnetic field produced by eddy currents induced in the specimen being tested. The presence of a crack disturbs the flow of the eddy currents, thus producing a magnetic field perturbation dependent on the position and shape of the defect itself. Variations in the electrical conductivity and magnetic permeability of the test object material, and the presence of defects in the object causes a change in eddy current and a corresponding change in phase and amplitude that can be detected by measuring the impedance changes in the magnetic field generating coil, which is a telltale sign of the presence of defects. The nature of the method is complex and there is therefore a need for deeper understanding that may be gained from mathematical models. Such models can have several objectives as for example procedure and equipment optimization or understanding of the method capability and reliability.

Physica Scripta, 2015

The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Res... more The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Research (FAIR) international project [1], which will be set up in Darmstadt in the next years, contains, among other magnets, several corrector magnets used for vertical and horizontal beam deviation. A prototype of a 2mrad vertical steerer magnet was designed by National Institute for R&D in Electrical Engineering (ICPE-CA) Romania in close cooperation with Forschungszentrum Julich Germany [2] and then manufactured and tested by ICPE-CA [3], Romanian Institute for Electrical Engineering—Advanced Research. Magnetic field measurements using a 3D Hall probe were performed. Measured data and their analysis are presented. The system used for Hall probe positioning and data acquisition is also described.

2015 9th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2015

This paper presents the analysis, characterization and optimization of a dipole magnet prototype ... more This paper presents the analysis, characterization and optimization of a dipole magnet prototype for The High-Energy Storage Ring (HESR) of the Facility for Antiproton and Ion Research (FAIR). Magnet design and construction, according to beneficiary requirements, are presented. A 2D magnetic modeling optimization of the magnetic pole shape is required in order to obtain a good homogeneity of the magnetic field in the center of the magnet. The numeric modeling is validated by magnetic measurements made on the considered prototype, using a measurement system with Hall Probe.

International Journal for Multiscale Computational Engineering, 2015

Accurate data about electric field on the metal-insulator interface are essential for a series of... more Accurate data about electric field on the metal-insulator interface are essential for a series of phenomena, such as electric breakdown, corona discharges, or electron emission. As the size of the structures used in electronics industry goes toward nanoscopic scale, the sharp edge electrostatic effect in these structures becomes more predominant and a correct estimation of the electric field intensity value implies using combined numerical and analytical methods. The implications of the theoretical obtained results are analyzed by considering experimental data.

Advanced Topics in Electrical …, 2011

The magnetization dynamics is described by a mathematical model that represents a time dependent ... more The magnetization dynamics is described by a mathematical model that represents a time dependent nonlinear differential equation, known as the Landau—Lifshitz—Gilbert equation (LLG). This paper investigates several numerical methods for solving different ...

Journal for Multiscale Computational Engineering / Begell House, Inc., 2015

Accurate data about electric field on the metal-insulator interface are essential for a series of... more Accurate data about electric field on the metal-insulator interface are essential for a series of phenomena, such as electric breakdown, corona discharges, or electron emission. As the size of the structures used in electronics industry goes toward nanoscopic scale, the sharp edge electrostatic effect in these structures becomes more predominant and a correct estimation of the electric field intensity value implies using combined numerical and analytical methods. The implications of the theoretical obtained results are analyzed by considering experimental data.

Physica Scripta, 2015

The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Res... more The High Energy Storage Ring (HESR), an important part of the Facility for Antiproton and Ion Research (FAIR) international project [1], which will be set up in Darmstadt in the next years, contains, among other magnets, several corrector magnets used for vertical and horizontal beam
deviation. A prototype of a 2mrad vertical steerer magnet was designed by National Institute for R&D in Electrical Engineering (ICPE-CA) Romania in close cooperation with Forschungszentrum Jülich Germany [2] and then manufactured and tested by ICPE-CA [3],
Romanian Institute for Electrical Engineering—Advanced Research. Magnetic field measurements using a 3D Hall probe were performed. Measured data and their analysis are presented. The system used for Hall probe positioning and data acquisition is also described.