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

Authors: Wang, Chenxu | Kawaguchi, Hideki

Article Type: Research Article

Abstract: To investigate portable, low power consumption, low cost and green high-performance computing (HPC) technologies which are suitable for industry applications, authors have been working on the development of dedicated computer based on dataflow architecture for electromagnetic field simulations. In this paper, we propose a Finite Integration Technique (FIT) dataflow machine based on BiCG-Stab scheme for 3-D electrostatic field simulations.

Keywords: HPC technologies, FIT, dataflow machine, BiCG-Stab, electrostatic field simulation

DOI: 10.3233/JAE-220147

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S8, 2022

Authors: Hagisaka, Ami | Niwa, Shotaro | Shiota, Shinya | Gao, Yanhui | Gotoh, Yuji

Article Type: Research Article

Abstract: At geothermal power plants, there is a problem that hot spring water pipes are blocked by the “hot spring scale”. The hot spring water used for geothermal power generation contains calcium, sulfur, and other substances, and the solid material called the “hot spring scale” adheres to the inside of steel pipes, significantly reducing the efficiency of steam transmission. In addition, there are maintenance costs to remove the “hot spring scale” inside the steel pipes. And it is important to evaluate the thickness of the hot spring scale inside the steel pipe. In this paper, a non-destructive sensor that is evaluated …the thickness of the hot spring scale inside the steel tube from the outside of the steel pipe is proposed. The proposed sensor is consisted of a permanent magnet, an alternating excitation coil and an acceleration sensor. The static magnetic field from the permanent, and eddy current inside the steel pipe are generated the vibration in the steel pipe. And the thickness of the hot spring scale is evaluated from this vibration intensity. It is shown that the thickness of hot spring scale from 0 mm to 15 mm can be inspected by this proposed method. In addition, the proposed inspection principle of this inspection method will be clarified by 3-D electromagnetic force analysis and displacement analysis. Show more

Keywords: Hot spring scale, electromagnetic force, electromagnetism vibration, steel material, electromagnetic 3-D FEM, displacement 3-D FEM

DOI: 10.3233/JAE-220207

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S9, 2022

Authors: Sun, Zhen | Sato, Takahiro | Watanabe, Kota

Article Type: Research Article

Abstract: A novel hybrid optimization (HO) method efficiently combines parameter optimization (PO) and topology optimization (TO) is proposed. The novelty concerns introducing the mesh deformation technique for model regeneration to make a connection between the TO and PO, in this way, the geometric features can be inherited in iterative optimization to fasten the convergence. The proposed HO is applied to the optimal design of a baseline V-type permanent magnet synchronous machine (PMSM), in which the topology of air barriers and the layout parameters of permanent magnets (PMs) are simultaneously optimized, for torque property enhancement. Comparative numerical results show that the proposed …HO is more efficient in optimal solution searching compared with traditional methods, as good topological features can be inherited in the iterative optimization. The numerical results also indicate that the proposed HO has good compatibility with different solvers, it can always provide good convergence to provide PMSM designs with excellent torque property when an evolutionary algorithm such as a genetic algorithm and evolution strategy is used as the solver. Show more

Keywords: Finite element analysis, gaussian distribution, mesh deformation algorithm, permanent magnet machine, topology optimization

DOI: 10.3233/JAE-220108

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S10, 2022

Authors: Liu, Qiao | Otomo, Yoshitsugu | Gong, Yunyi | Igarashi, Hajime

Article Type: Research Article

Abstract: The resistance and inductance of an inductor working at high frequencies depend on frequency because of eddy currents caused by the skin and proximity effects. In addition, the stray capacitance among winding coils would give significant influence. This paper proposes an equivalent circuit model which can consider the displacement and eddy currents simultaneously in frequency and time domain. In the proposed circuit model, the capacitance and complex inductance are determined by solving electrostatic and magnetostatic equations with finite element method (FEM). It is shown that the input impedance of an air-core coil is consistent with that computed by FEM at …low frequencies. Moreover, the former is shown to be consistent with the measured result. Show more

Keywords: Inductor, equivalent circuit, eddy current, displacement current, self-resonant

DOI: 10.3233/JAE-220160

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S8, 2022

Authors: Tanaka, Yoshikazu | Simojyo, Kazuki

Article Type: Research Article

Abstract: The magnetic targeting method is expected for the regeneration of cartilage of knee. Magnetically labeled mesenchymal stem cells (m-MSCs) and an external magnetic field are used in the magnetic targeting method. A numerical calculation method for simulating the behavior of the m-MSC is needed. In this paper a numerical calculation method of magnetization and eddy current by applying the subdomain method to integral equations is presented. The proposed method has been used to solve two problems for which the exact solutions are known, namely the magnetization of a sphere placed in a uniform magnetic field and the eddy current induced …in a flat plate, to verify its validity. Through the two problems, the validity of the proposed method has been confirmed. Show more

Keywords: m-MSCs, integral equations, subdomain method, magnetization, eddy current

DOI: 10.3233/JAE-220117

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S10, 2022

Authors: Hirose, Soichiro | Nguyen, Dang Trang | Taguchi, Kozo

Article Type: Research Article

Abstract: The performance of soil microbial fuel cells (SMFCs) is greatly affected by the material of the anode. In this study, a low-cost material was fabricated based on rice husk charcoal (RHC) and cheaply available Bokuju (Japanese black drawing ink). Using the fabricated material to make the anode, the SMFC obtained a maximum power density of 9.52 μW/cm2 . RHC showed a significant impact on the performance of the anode electrodes. Also, the ratio of RHC to Bokuju affected the output of the SMFC.

Keywords: Soil microbial fuel cell, rice husk, Bokuju

DOI: 10.3233/JAE-220189

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S8, 2022

Authors: Nakamoto, Hiroyuki | Terada, Kazuma | Guy, Philippe | Uchimoto, Tetsuya

Article Type: Research Article

Abstract: Flow accelerated corrosion generates not only pipe-wall thinning but also roughness on an inside wall. In some flow conditions, the increase in roughness can increase the mass transfer coefficient by up to 80%. It is then very important to have an evaluation tool to monitor and quantify the roughness of a pipe. This study aims to estimate the roughness by using ultrasonic attenuation. The advantage of using ultrasonic attenuation is that it utilizes the signals measured by existing ultrasonic probes, and does not require significant changes to the equipment. To evaluate the inner rough surface, this study compares ultrasonic attenuations …on random and periodic rough surfaces. We used an ultrasonic broadband probe on specimens with random and periodic rough surfaces in experiments. The results indicate a significant difference between the attenuation values estimated on random and periodic roughness. In addition, attenuation of amplitude at specific frequencies also was observed. These specific frequencies implied having the potential to estimate the pitch of periodic flaws on the rough surface. Show more

Keywords: Nondestructive testing, ultrasonic attenuation, rough surface

DOI: 10.3233/JAE-220196

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S8, 2022

Authors: Ukwungwu, David | Leuning, Nora | Hameyer, Kay

Article Type: Research Article

Abstract: In this paper, an efficiency improvement of a high-speed permanent magnet excited synchronous machine (PMSM) by the use of spot-welding as lamination packaging technology is realized. Welding, interlocking, clinching and gluing are typical technologies to manufacture electrical steel stacks of electrical machines. However, these processes deteriorate the magnetic properties of the steel sheets, thereby decreasing the overall efficiency of the machine. Variations of line-welding (six, eight, twelve, thirty two and forty) line welds and spot-welding procedure is performed and analyzed. A semi-physical iron loss separation approach is used to extract the IEM iron loss model (Eggers et al., IEEE Transactions …on Magnetics 48 (11) (2012), 3021–3024). These parameters are utilized during the finite element simulation to calculate the effective iron loss (efficiency) of the machine while using each joining procedure. A low speed, high-speed and WLTC-c3 driving cycle is exemplarily used to analyze the effects of each procedure on the machine efficiency at the different operating conditions. Show more

Keywords: Welding process, ferro-magnetic lamination, numerical simulation, electrical steel

DOI: 10.3233/JAE-220125

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S12, 2022

Authors: Wang, Ning | Zhao, Wenliang | Li, Min | An, Ningning

Article Type: Research Article

Abstract: This paper deals with the design and analysis of a surface-mounted outer rotor in-wheel motor (IWM) with the aim of reducing cogging torque and torque ripple for electric vehicles. The proposed IWM is equipped with axial sinusoidal surface-mounted permanent magnets (PMs), with the purpose of producing sinusoidal air gap flux density distribution, thus to realize sinusoidal back electromotive force (EMF) and smooth electromagnetic torque. To highlight the advantage of the proposed IWM, the conventional IWM with tile-shaped PMs and the IWM with stepwise-shaped PMs are also studied for comparison. The finite element method in the commercial software package is utilized …to analyze the performance of the three motors, including the radial flux density of air gap, back EMF, cogging torque, and electromagnetic torque. Through the quantitative comparison, it is found that the proposed IWM greatly reduces the cogging torque, highly improves the sinusoidality of back EMF, and nearly eliminates the torque ripple. Show more

Keywords: In-wheel motor, sinusoidal permanent magnet, air gap flux density, cogging torque, torque ripple

DOI: 10.3233/JAE-220211

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S10, 2022

Authors: Jankowski, Piotr | Piłat, Andrzej | Wołoszyn, Joanna

Article Type: Research Article

Abstract: In the paper the results of research on an ultra-fast actuator with high initial energy were presented. The purpose of this research is to determine the critical parameters of a copper coil and a double-layer disc based on magneto-thermal analysis. The determined parameters must ensure the expected dynamics of the moving disc while not exceeding the allowable coil and disc temperature.

Keywords: Actuator, inductive dynamic drive, ultra rapid hybrid breaker

DOI: 10.3233/JAE-220203

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. Pre-press, no. Pre-press, pp. S1-S8, 2022