International Journal of Applied Electromagnetics and Mechanics - Volume Pre-press, issue Pre-press

Authors: Kikuchi, Hiroaki | Sato, Yuki

Article Type: Research Article

Abstract: We investigated effects of contact gap on magnetic nondestructive evaluation technique using a magnetic single-yoke probe. Firstly, we evaluated hysteresis curves and impedance related to permeability of the material measured by a single-yoke probe, when an air gap length between the probe and specimens changes. The hysteresis curve gradually inclines to the axis of the magneto-motive force and magneto-motive force at which the magnetic flux is 0 decreases with increasing the gap length. The effective permeability also decreases with increasing the gap thickness. The incremental of gap thickness increases the reluctance inside the magnetic circuit composed of the yoke, specimen …and gap, which results in the reduction of flux applying to specimen. Show more

Keywords: Magnetic NDE, magnetic yoke probe, contact gap, coercive field, permeability, impedance, magneto-motive force

DOI: 10.3233/JAE-209411

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2020

Authors: Hosokawa, Hiroyuki | Hirata, Katsuhiro | Niguchi, Noboru

Article Type: Research Article

Abstract: We propose a non-contact electromagnetic impact-torque device (EMI device) using induced currents, and its characteristics have been verified using 3-D finite element method (FEM) analysis and carrying out measurements on a prototype. This paper describes a new EMI device with a regenerative circuit. A boosting chopper circuit is connected to the proposed EMI device, and the impact torque is controlled using the regenerated power.

Keywords: Electromagnetic impact-torque device, boosting circuit, finite element method

DOI: 10.3233/JAE-209431

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2020

Authors: Kato, Hirohisa | Komori, Mochimitsu | Asami, Ken-ichi | Sakai, Nobuo

Article Type: Research Article

Abstract: In this paper, a centrifugal pump for for extremely low temperature was fabricated and evaluated by experiments in liquid nitrogen. The pump is using a bearingless motor and permanent magnet bearings to levitate and rotate the rotor without lubricating oil. The difference from the conventional study is that a one-axis controlled bearingless motor is used to reduce the magnetic bearing cost and that the bearings are installed in the liquid to eliminate a shaft-seal. Stable levitation and rotation of the rotor were confirmed in the rotation and pump experiments in liquid nitrogen. In pump experiment, the flow rate of liquid …nitrogen was measured at 1 cm in a pumping height. The maximum flow rate was 1.3 L/min when the rotation speed is 1,800 rpm. Show more

Keywords: Magnetic bearing, bearingless motor, centrifugal pump, low temperature, actuator

DOI: 10.3233/JAE-209447

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2020

Authors: Chen, Tao | Xiao, Xiaoqi | Zhang, Lihong | Lv, Cheng | Deng, Zhiyang | Song, Xiaochun

Article Type: Research Article

Abstract: Due to uneven surface and lift-off effect, it is difficult to detect weld crack by eddy-current testing. A new orthogonal eddy-current probe for weld crack detection of carbon-steel plate was designed in this paper. Based on COMSOL Multiphysics, the influence of scanning angle on detection sensitivity of the probe was compared firstly. Then, the effects of coil width, coil side length, detection coil height, and lift-off distance on detection sensitivity of the probe were studied, respectively. Finally, the test piece of carbon-steel plate weld with crack, and the physical probe used to verify the crack detection effect were made. The …experimental results show that the weld crack of carbon-steel plate with length × width × depth of 20.0 mm × 0.3 mm × 1 mm can be effectively identified, and the lift-off noise can be effectively suppressed by the method presented in this paper. At the same time, the signal-to-noise ratio of the probe keeps constant in the lift-off distance range of 0.3 mm–3.0 mm. Show more

Keywords: Orthogonal eddy-current probe, carbon-steel weld, nondestructive testing, COMSOL multiphysics

DOI: 10.3233/JAE-209453

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2020

Authors: Wang, Li | Chen, Zhenmao

Article Type: Research Article

Abstract: In the nondestructive evaluation for components of key equipment, sizing of natural crack is important in order to guarantee both the safety and efficient operation for large mechanical systems. Natural cracks have complex boundary and there may be electric current flowing through crack faces. If a simple model of artificial notch is used to simulate it, errors often occur in crack depth reconstruction from eddy current testing (ECT) signals. However, if a complex crack conductivity model is used, quantitative evaluation of natural crack will be transformed into a multivariable nonlinear optimization problem and the solution is difficult. In this paper, …based on the relationship between crack parameters and features of multi-frequency ECT signals, a multi-output support vector regression algorithm using domain decomposition for parameters was proposed The algorithm realized the quantitative evaluation of multiple parameters of crack in turn. Numerical examples with simulated and measured ECT signals were presented to verify the efficiency of the proposed strategy. Show more

Keywords: Quantitative evaluation, natural crack, eddy current testing, support vector regression, multivariable output

DOI: 10.3233/JAE-209383

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-8, 2020

Authors: Sato, Hayaho | Maruo, Akito | Igarashi, Hajime

Article Type: Research Article

Abstract: This paper presents the three-dimensional modeling of soft magnetic composite (SMC) based on the discrete element method. The proposed method makes it possible to take the possible contact among the magnetic particles in SMC as well as the distributed particle size into consideration. Based on this modeling, the macroscopic B -H characteristics is computed with the finite element method considering magnetic saturation. It is shown that the three-dimensional model of SMC can have larger initial permeability in comparison with the two-dimensional model even if they have the same filling factor.

Keywords: Discrete element method, homogenization method, soft magnetic composite

DOI: 10.3233/JAE-209355

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2020

Authors: Chen, Yuanyuan | Jin, Wuyin | Wang, Meng

Article Type: Research Article

Abstract: A novel deep learning segmentation method based on Conditional Generative Adversarial Nets (CGAN) is proposed, being U-GAN in this paper to overtake shortcomings of the metallographic images of GCr15 bearing steel, such as multi-noise, low contrast and difficult to segment. The results of experiment indicate that the proposed model is the most accurate comparing with the digital image processing methods and deep learning methods on carbide particle segmentation. The average Dice’s coefficient of similarity measure function is 0.9158, which is the state-of-the-art performance on dataset.

Keywords: Metallographic image, image processing, carbide particle segmentation, deep learning, CGAN

DOI: 10.3233/JAE-209441

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-7, 2020

Authors: Xu, Fangchao | Guo, Yongquan | Zhou, Ran | Jin, Junjie | Zhao, Chuan | Zhang, Xiaoyou | Sun, Feng

Article Type: Research Article

Abstract: To solve the problem of reduction of suspension force of permanent magnet system with variable magnetic flux path control, according to the structure of the system, suspension principle of the permanent magnet system with variable magnetic flux path control and the generation principle of the load torque, the influence of the mechanical structure of the system on the suspension force is analyzed by changing part of parameters of the system structure. The results show that the existence of magnetic isolation plate is the main reason for the decrease of suspension force, the permanent magnet ring can be thickened to 11.91 mm, …the annular gap can be reduced to 1 mm, thickness of the “F” shaped magnetizer can be increased to 9 mm to increase the suspension force. Show more

Keywords: Magnet system, variable magnetic flux path, analysis of structure factor

DOI: 10.3233/JAE-209470

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-10, 2020

Authors: Dong, Yangyang | Zuo, Kungang | Han, Shaojie | Zhang, Zijian

Article Type: Research Article

Abstract: Piezoelectric Stack Actuators (PEAs) have been widely used in high-precision positioning system because of its fast response. However, under different excitation voltages and external loads with dynamic frequencies, the width and inclination of PEAs hysteresis curves verified correspondingly, and exhibit asymmetry phenomenon. The main contribution of this paper is to present a two-input asymmetric dynamic cross-coupled hysteresis (TADCH) model to describe the complex nonlinear hysteresis of PEAs in dynamic excitation and loading engineering applications. Moreover, we also develop the corresponding identification method of TADCH model. Finally, several experiments are carried out to verify the accuracy of the proposed model.

Keywords: Prandtl–Ishlinskii hysteresis, two-input dynamic cross-coupled asymmetric hysteresis

DOI: 10.3233/JAE-209469

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2020

Authors: Ito, Yasuaki | Oda, Yoshiho | Kato, Taro | Liu, Xiaojun | Endo, Ayato | Ikeda, Keigo | Narita, Takayoshi | Kato, Hideaki

Article Type: Research Article

Abstract: Thin steel plates are widely used in various industrial products. However, because of the deterioration of surface quality and metal plating that occurs during transport, some problems exist. As a solution to these problems, a noncontact transport of steel plate using electromagnetic force has been proposed. However, side slip or the dropping of the plate may occur. Therefore, we proposed the addition of electromagnetic actuators to control the horizontal motion of levitated steel plates. In this study, we examined the change in the levitation stability during noncontact transport with the addition of positioning control in the horizontal direction or changed …transport conditions. As a result, the application of a magnetic field in the horizontal direction improved the levitation stability of transported thin steel plates in different transport conditions. Show more

Keywords: Electromagnetic levitation control, thin steel plate, vibration control, magnetic field, transportation

DOI: 10.3233/JAE-209369

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. 1-9, 2020