scholarly journals Noncontact Guide System for Traveling Continuous Steel Plate Using Electromagnet and Supplement of Permanent Magnets for Suppressing Vibration

Actuators ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 47 ◽  
Author(s):  
Takahiko Bessho ◽  
Sora Ishihara ◽  
Yasuhiro Narawa ◽  
Ryo Yamaguti ◽  
Takayoshi Narita ◽  
...  
Keyword(s):  
High Speed ◽  
Permanent Magnets ◽  
Steel Plate ◽  
Vertical Direction ◽  
Mode Analysis ◽  
Steady Current ◽  
Guide System ◽  
Current Value ◽  
Increase In Productivity ◽  
Stable Control

In a plating process, the steel plate is conveyed 20–50 m in the vertical direction for drying, during which it is negligibly supported by rollers and other mechanisms. This produces plating without uniformity owing to the generation of vibration and other factors, which prevent the increase in productivity. We have developed a noncontact guide system for a high-speed traveling elastic steel plate in which electromagnetic forces are applied by actuators at the edges of the plate to control the plate’s position. In this study, we investigated the vibration phenomenon when changing the steady current value of the electromagnet used for controlling the position. In addition, we conducted mode analysis of the steel plate to enable stable control even at low steady current values and verified whether stable guide can be provided by using it together with a permanent magnet. As a result, by arranging the permanent magnets, stable guidance was possible even at a low steady current value. In addition, it became clear that vibration damping performance is also improved.

Study on Magnetic Barrel Machine Equipped with Three-Dimensional Arrangement of Magnets

2007 ◽  
Vol 329 ◽  
pp. 761-766 ◽  
Author(s):  
Y. Zhang ◽  
Masato Yoshioka ◽  
Shin-Ichiro Hira
Keyword(s):  
High Speed ◽  
Permanent Magnets ◽  
Three Dimensional ◽  
Video Camera ◽  
High Speed Video ◽  
High Speed Video Camera ◽  
The Media ◽  
Set Up

At present, a commercially available magnetic barrel machine equipped with permanent magnets has some faults arising from constructional reason. That is, grinding or finishing ability is different from place to place in the machining region, resulting in the limitation on the region we can use in the container of workpieces. Therefore, in this research, authors made the new magnetic barrel machine equipped with three dimensional (3D) magnet arrangement to overcome these faults. The grinding ability of the new 3D magnetic barrel machine converted was experimentally examined, and compared with that of the traditional magnetic barrel machine. As a result, it was shown that we can use much broader region in the new 3D machine. It was also shown that the grinding ability became higher. The distribution of barrel media in action was recorded by means of a high speed video camera. It was clarified that the media rose up higher and were distributed more uniformly in the container by the effect of the magnet block newly set up. It was supposed that this must be the reason for the above-mentioned improvement of grinding ability.

scholarly journals A Study on the Energy-Harvesting Device with a Magnetic Spring for Improved Durability in High-Speed Trains

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 830
Author(s):  
Jaehoon Kim
Keyword(s):  
Energy Harvesting ◽  
High Speed ◽  
Permanent Magnets ◽  
Critical Issue ◽  
Sensor Nodes ◽  
High Speed Train ◽  
Vibration Energy Harvesting ◽  
Magnetic Spring ◽  
High Speed Trains ◽  
Energy Harvesting Devices

Durability is a critical issue concerning energy-harvesting devices. Despite the energy-harvesting device’s excellent performance, moving components, such as the metal spring, can be damaged during operation. To solve the durability problem of the metal spring in a vibration-energy-harvesting (VEH) device, this study applied a non-contact magnetic spring to a VEH device using the repulsive force of permanent magnets. A laboratory experiment was conducted to determine the potential energy-harvesting power using the magnetic spring VEH device. In addition, the characteristics of the generated power were studied using the magnetic spring VEH device in a high-speed train traveling at 300 km/h. Through the high-speed train experiment, the power generated by both the metal spring VEH device and magnetic spring VEH device was measured, and the performance characteristics required for a power source for wireless sensor nodes in high-speed trains are discussed.

Stress and Vibration Analysis of Motor Back Plate in HDD

2011 ◽  
Vol 275 ◽  
pp. 97-100 ◽  
Author(s):  
Geun Sub Heo ◽  
Oh Hyun Kang ◽  
Cheol Woo Park ◽  
Sang Ryong Lee ◽  
Choon Young Lee
Keyword(s):  
Resonant Frequency ◽  
High Speed ◽  
Vibration Mode ◽  
Hard Disk Drives ◽  
Mode Analysis ◽  
Design Parameters ◽  
Disk Drives ◽  
Ansys Software ◽  
Back Plate ◽  
Plate Shape

In the present study, we have simulated stress characteristics and vibration modes in the back plate of head-stack driving motor of 2.5 inch small sized hard disk drives (HDDs). The magnets in head-stack driving motor have large magnetic fields, and therefore, the resulting large force may induce fracture and deformation in the back plate of the motor. Since the high-speed motion of head-stack motor generates high frequency vibration, we analyzed the vibration mode to avoid resonant frequency. ANSYS software was used in this study to check the deformation of back plate with the following design parameters: thickness of plate, the number of support beams, and the width of support beams. From the vibration mode analysis, we obtained a stable plate shape whose operating frequency is off the resonant frequency.

scholarly journals World Experience in Creating Mathematical Models of Air Springs: Advantages and Disadvantages

2021 ◽  
pp. 25-42
Author(s):  
A. Y Kuzyshyn ◽  
S. A Kostritsia ◽  
Yu. H Sobolevska ◽  
А. V Batih
Keyword(s):  
Mathematical Model ◽  
Finite Element ◽  
Mathematical Models ◽  
Dynamic Behavior ◽  
High Speed ◽  
Vertical Direction ◽  
Rolling Stock ◽  
Air Spring ◽  
Advantages And Disadvantages ◽  
Mechanical Models

Purpose. Taking into account the production and commissioning of modern high-speed rolling stock, the authors are aimed to analyze the currently created mathematical models describing the dynamic behavior of the air spring, systematize them and consider the advantages and disadvantages of each model type. Methodology. For the analysis, a comparative chronological method was used, which makes it possible to trace the development of several points of view, concepts, theories. In accordance with the adopted decision equations, the existing models of air springs were divided into three groups: mechanical, thermodynamic and finite-elements. When analyzing mathematical models, the influence of a number of parameters on the dynamic behavior of the air spring, such as disturbing force frequency, heat transfer, nonlinear characteristics of materials, the shape of the membrane, etc., was considered. Findings. A feature of mechanical models is the determination of input parameters based on the analysis of experimental results, requires access to complex measuring equipment and must be performed for each new model of an air spring separately. Unlike mechanical models, which allow taking into account the damping effect of an air spring in the horizontal and vertical direction, thermodynamic models are mainly focused on studying the dynamic behavior of an air spring in the vertical direction. The use of the finite element method makes it possible to most accurately reproduce the dynamic behavior of an air spring, however, it requires significant expenditures of time and effort to create a finite element model and perform calculations. Originality. Mathematical models of the dynamic behavior of an air spring are systematized, and the importance of their study in conjunction with a spatial mathematical model of high-speed rolling stock is emphasized. Practical value. The analysis of the mathematical models of the dynamic behavior of the air spring shows the ways of their further improvement, indicates the possibility of their use in the spatial mathematical model of the rolling stock in accordance with the tasks set. It will allow, even at the design stage of high-speed rolling stock, to evaluate its dynamic characteristic and traffic safety indicators when interacting with a railway track.

scholarly journals High-Temperature Superconducting Non-Insulation Closed-Loop Coils for Electro-Dynamic Suspension System

Electronics ◽  
2021 ◽  
Vol 10 (16) ◽  
pp. 1980
Author(s):  
Li Lu ◽  
Wei Wu ◽  
Xin Yu ◽  
Zhijian Jin
Keyword(s):  
High Temperature ◽  
Liquid Helium ◽  
High Speed ◽  
Closed Loop ◽  
Permanent Magnets ◽  
Superconducting Magnets ◽  
Current Mode ◽  
Persistent Current ◽  
Magnetomotive Force ◽  
High Temperature Superconducting

The null-flux electro-dynamic suspension (EDS) system is a feasible high-speed maglev system with speeds of above 600 km/h. Owing to their greater current-carrying capacity, superconducting magnets can provide a super-magnetomotive force that is required for the null-flux EDS system, which cannot be provided by electromagnets and permanent magnets. Relatively mature high-speed maglev technology currently exists using low-temperature superconducting (LTS) magnets as the core, which works in the liquid helium temperature region (T ⩽ 4.2 K). Second-generation (2G) high-temperature superconducting (HTS) magnets wound by REBa2Cu3O7−δ (REBCO, RE = rare earth) tapes work above the 20 K region and do not rely on liquid helium, which is rare on Earth. In this study, the HTS non-insulation closed-loop coils module was designed for an EDS system and excited with a persistent current switch (PCS). The HTS coils module can work in the persistent current mode and exhibit premier thermal quenching self-protection. In addition, a full-size double-pancake (DP) module was designed and manufactured in this study, and it was tested in a liquid nitrogen (LN2) environment. The critical current of the DP module was approximately 54 A, and it could work in the persistent current mode with an average decay rate measured over 12 h of 0.58%/day.

scholarly journals Turbulent channel flow over an anisotropic porous wall – drag increase and reduction

2018 ◽  
Vol 842 ◽  
pp. 381-394 ◽  
Author(s):  
Marco E. Rosti ◽  
Luca Brandt ◽  
Alfredo Pinelli
Keyword(s):  
Drag Reduction ◽  
Channel Flow ◽  
High Speed ◽  
Vertical Direction ◽  
Porous Wall ◽  
Turbulent Channel Flow ◽  
Spanwise Direction ◽  
Normal Velocity ◽  
Porous Walls ◽  
The One

The effect of the variations of the permeability tensor on the close-to-the-wall behaviour of a turbulent channel flow bounded by porous walls is explored using a set of direct numerical simulations. It is found that the total drag can be either reduced or increased by more than 20 % by adjusting the permeability directional properties. Drag reduction is achieved for the case of materials with permeability in the vertical direction lower than the one in the wall-parallel planes. This configuration limits the wall-normal velocity at the interface while promoting an increase of the tangential slip velocity leading to an almost ‘one-component’ turbulence where the low- and high-speed streak coherence is strongly enhanced. On the other hand, strong drag increase is found when high wall-normal and low wall-parallel permeabilities are prescribed. In this condition, the enhancement of the wall-normal fluctuations due to the reduced wall-blocking effect triggers the onset of structures which are strongly correlated in the spanwise direction, a phenomenon observed by other authors in flows over isotropic porous layers or over ribletted walls with large protrusion heights. The use of anisotropic porous walls for drag reduction is particularly attractive since equal gains can be achieved at different Reynolds numbers by rescaling the magnitude of the permeability only.

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