International Journal of Applied Electromagnetics and Mechanics - Volume 46, issue 1

Authors: Bekinal, Siddappa Iranna | rao Anil, Tumkur Ramakrishna | Jana, Soumendu

Article Type: Research Article

Abstract: This paper presents a simple mathematical model to determine the three dimensional (3D) magnetic field components in Permanent Magnet (PM) bearings made of ring magnets with axial, radial and perpendicular polarizations. MATLAB codes are written to evaluate the magnetic field components using Coulombian model and simple vector approach. In addition, the effect of axial, radial and angular displacements (five degrees of freedom) of the rotor magnet ring on the magnetic field created by the ring magnets …in PM bearings is presented. Finally, the effect of movement of the outer ring magnet on the magnetic field created by two rings in the air gap is discussed. Show more

Keywords: Angular displacement, Coulombian model, magnetic field components, vector approach, permanent magnet

DOI: 10.3233/JAE-141776

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 255-269, 2014

Authors: Su, Hao | Chen, Ming

Article Type: Research Article

Abstract: Tension tests were conducted on 45# steel to investigate metal magnetic memory in stress concentration areas. The normal and tangential components of metal magnetic memory signals at seven test points in each specimen were simultaneously measured with probe lift-off values of 1 mm, 3 mm, and 5 mm. Axial tensile load was applied until visible necking occurred, and magnetic flux density was compared with the fracture location predicted according to Doubov's theory. Experimental results showed that …the final fracture locations were inconsistent with the locations predicted by metal magnetic memory testing theory. A theoretical analysis of the determination criterion in Doubov's theory also revealed that no perfect correlation between the two areas existed. Show more

Keywords: Metal, magnetic, memory, stress, concentration, tension, test

DOI: 10.3233/JAE-141777

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 271-280, 2014

Authors: Nouicer, Abdelmadjid

Article Type: Research Article

Abstract: This paper presents a new approach for incorporating the thermal effect on the magnetic hysteresis of the 3F3 material. The proposed algorithm is based on the knowledge of the magnetic flux density spectrum for some temperatures. So, a feed-forward neural network is trained to learn the relation between the rank of harmonics, the temperature and the amplitude of each harmonic. To construct the hysteresis loop for a new value of the temperature, the neural network predicts …the spectrum of the magnetic flux density B which is transformed back to the time domain. Show more

Keywords: Discrete fourier transform (DFT), ferrite 3f3 material, magnetic hysteresis, neural networks, thermal behaviour

DOI: 10.3233/JAE-141778

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 281-286, 2014

Authors: Cheng, Yuhua | Shu, Yaming

Article Type: Research Article

Abstract: The mutual inductance between the transmitted and received coils is an important parameter in the inductively coupled wireless power transmission system. The relative position between the linked coils may be arbitrary according to the applications. In this paper the analytical calculation of the mutual inductance between two arbitrarily positioned rectangular filaments is proposed based on a more general expression of mutual inductance calculation of two arbitrarily positioned straight filaments than Grover's. The calculation …results are validated by using the finite element simulation tools. The previous published approximation methods for square coils in the coaxial, lateral misalignment or angular misalignment situations are verified that they are accurate when the two coils' relative distances are large. Show more

Keywords: Mutual inductance, rectangular filament, arbitrary position

DOI: 10.3233/JAE-141779

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 287-298, 2014

Authors: Zhou, Rougang | Zhou, Yunfei | Liu, Guangdou | Lu, Jianyin | Cheng, Xin

Article Type: Research Article

Abstract: Magnetically levitated planar actuators can simplify the planar motion mechanism and thus realize high-speed and high-accuracy motion. The accuracy in the shape of coil, a core part of magnetically levitated planar actuator, is crucial to the performance of actuator. Although the foil-wound coil has high forming precision, the strong eddy current generated in the motion of actuator may pose great interference to magnetic levitation and deteriorate system stability. Based on a thorough analysis of the eddy …current and eddy-current force of foil-wound coils in the magnetically levitated planar motion, the paper proposes the calculation model for disturbing eddy force. Results from the simulation show that the model has a relatively high accuracy. It is also indicated that further predictive compensation for the eddy force in the control of precise magnetically levitated actuators can increase the kinematic accuracy and stability of magnetically levitated planar motion system. Show more

Keywords: Magnetic levitated planar actuators, foil-wound coil, eddy-current, eddy current force, halbach permanent magnet array

DOI: 10.3233/JAE-141780

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 299-312, 2014

Authors: Sun, Tongsheng

Article Type: Research Article

Abstract: In order to improve energy conversion efficiency of asphalt mixture during microwave heating, key characteristic parameters are researched. Attenuation law of electric field intensity and dielectric loss in asphalt mixture are discussed and conversion model between thermal field and electric field is built. Results show that: (1) electric field intensity attenuates with the increase of the measuring depth of microwave, and the utilization rate of electromagnetic energy increases with attenuation constant; (2) electric field …intensity also attenuates with the increase of dielectric permittivity and dielectric loss tangent of asphalt mixture; (3) temperature of asphalt mixture can be significantly improved by enhancing intensity of internal heat source. The findings can provide the theoretical basis for selection of asphalt pavement material, establishment of microwave recycling theory and design of microwave heating equipments. Show more

Keywords: Asphalt mixture, microwave heating, dielectric loss, electric field intensity, dielectric permittivity

DOI: 10.3233/JAE-141968

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 46, no. 1, pp. 313-323, 2014