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Dynamic analysis of traction motor in a locomotive considering surface waviness on races of a motor bearing

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Railway Engineering Science 2021年第4期29卷 379-393页

作者： Yuqing Liu Zaigang Chen Wei Li Kaiyun Wang State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Motor Technology Department CRRC Yongji Motor Co.Ltd.Xi’an 710018China

The traction motor is the power source of the *** the surface waviness occurs on the races of the motor bearing,it will cause abnormal vibration and noise,accelerate fatigue and wear,and seriously affect the stability and safety of the traction power *** this paper,an excitation model coupling the time-varying displacement and contact stiffness excitations is adopted to investigate the effect of the surface waviness of the motor bearing on the traction motor under the excitation from the locomotive-track coupled *** detailed mechanical power transmission path and the internal/external excitations(e.g.,wheel–rail interaction,gear mesh,and internal interactions of the rolling bearing)of the locomotive are comprehensively considered to provide accurate dynamic loads for the traction *** of the wavenumber and amplitude of the surface waviness on the traction motor and its neighbor components of the locomotive are *** results indicate that controlling the amplitude of the waviness and avoiding the wavenumber being an integer multiple of the number of the rollers are helpful for reducing the abnormal vibration and noise of the traction motor.

关键词： Rolling bearing Traction motor waviness Vibration responses Vehicle-track coupled dynamics

Analysis of Friction Torque Properties and Evaluation of waviness Based on Couple-joints Angular Contact Ball Bearings for Aerospace Field

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Analysis of Friction Torque Properties and Evaluation of Wav...

Quantification methodologies on organization and morphology features of fiber-like structures:A review

2010 International Symposium on Inertial Technology and Navigation

作者： ZHANG Xiao-ning XU Feng-mi (Institute No.16 of China Aerospace Academe No.9 Xi’an 710100 China)

＜正＞In view of couple-joints angular contact ball bearings for aerospace field,we simulated various status testing and monitored running ***,we analyzed friction torque properties of back-to-back arrangement *** then we evaluated waviness of friction torque *** results show that the analysis method and evaluation measurement are correct and feasible. Therefore,it is guaranteed that the rotated accuracy of the shafting and thereof resist at a high level, moreover it ensures the accuracy of the overall structure system.

关键词： angular contact ball bearings platform friction torque properties waviness

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创新光学健康科学杂志(英文) 2023年第4期16卷 1-19页

作者： Chuncheng Wang Jia Meng Shuhao Qian Lingxi Zhou Shenyi Jiang Rushan Jiang Hantao Zhan Xinguo Fang Yijie Liu Zhihua Ding Zhiyi Liu State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering International Research Center for Advanced Photonics Zhejiang University Hangzhou Zhejiang 310027P.R.China Intelligent Optics&Photonics Research Center Jiaxing Research Institute Zhejiang University JiaxingZhejiang 314000P.R.China

Among all the structural formations,fiber-like structure is one of the most common modalities in organisms that undertake essential *** in spatial organization of fibrous structures can refiect information of physiological and pathological activities,which is of significance in both researches and clinical ***,the quantification of subtle changes in fiber-like structures is potentiallymeaningful in studying structure-function relationships,disease progression,carcinoma staging and engineered tissue *** this study,we examined a wide range of methodologies that quantify organizational and morphological features of fibrous structures,including orientation,alignment,waviness and *** method was demonstrated with specific ***,perspectives of future quantification analysis techniques were explored.

关键词： Biophotonics orientation waviness thickness fiber-like structure

Frictional shear stress of ZnO nanowires on natural and pyrolytic graphite substrates

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Friction 2022年第12期10卷 2059-2068页

作者： Lizhen HOU Maofen HOU Tursunay YIBIBULLA James Lee MEAD Sergej FATIKOW Shiliang WANG Han HUANG Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education School of Physics and Electronic ScienceHunan Normal UniversityChangsha 410081China School of Physics and Electronics Central South UniversityChangsha 410083China Division Microrobotics and Control Engineering Department of Computing ScienceUniversity of OldenburgOldenburg D-26129Germany School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQLD 4072Australia

The friction behaviour of ZnO nanowires on natural graphite(NG)and highly oriented pyrolytic graphite(HOPG)substrates was tested in ambient conditions by use of optical microscopy based *** on the step-free and waviness-free NG substrate exhibit a diameter-independent nominal frictional shear stress of 0.48 MPa,and this provides a benchmark for studying how the surface topography of graphite influences nanowire *** on the HOPG substrate present a significant diameter-dependent frictional shear stress,increasing from 0.25 to 2.78 MPa with the decrease of nanowire diameter from 485 to 142 *** waviness of HOPG has a limited effect on the nanowire friction,as a nanowire can fully conform to the *** surface steps on the HOPG can significantly enhance the nanowire friction and lead to a much higher frictional shear stress than that on NG due to mechanical blocking and the presence of a Schwoebel barrier at step *** surface steps,however,can also generate small wedge-shaped gaps between a nanowire and substrate,and thus reduce the nanowire *** the decrease in nanowire diameter,the capacity for the nanowire to better conform to the substrate reduces the length of the wedge-shaped gaps,leading to the observed increase in nanowire *** results have improved our understanding of the unique friction behaviour of *** an improved understanding is expected to benefit the design and operation of nanowire-friction-based devices,including bio-inspired fibrillar adhesives,soft grippers,rotary nanomotors,and triboelectric nanogenerators.

关键词： frictional shear stress nanowires graphite surface step waviness

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曾丹和她的时装

今日中国 1994年第5期43卷 37-42页

作者：李霞

曾丹和她的时装李霞“时装就是模特们穿了在舞台上表演的服装，”老百姓说。“时装就是老百姓喜欢穿的、正在流行的服装，”曾丹说。曾丹是时下正在京城走红的服装设计师，她的名字常见于报端，她设计的服装在不少商场开了专柜出售。由... 详细信息

曾丹和她的时装李霞“时装就是模特们穿了在舞台上表演的服装，”老百姓说。“时装就是老百姓喜欢穿的、正在流行的服装，”曾丹说。曾丹是时下正在京城走红的服装设计师，她的名字常见于报端，她设计的服装在不少商场开了专柜出售。由高贵趋向平实，因人因时而宜是曾丹时...

关键词： grinding wheel unbalance waviness

Effect of Cutting Speed on Surface Quality by Bandsawing

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Journal of Forestry Research 1997年第4期8卷 246-249页

作者：于建国 LiangkaiTING DepartmentofScienceandEngineering ShimaneUniversity

The surface profile behavior of workpieces sawn has been investigated. Six species were sawn under the condi-tion of four different kinds of cutting speed by the band saw. The real surface profile of a sawn workpiecc is composed of twosections, which arc the additivity of the waviness of filtered wave and roughness curve. The roughness of center line avernge aswell as amplitude decrease with the increasing of cutting speed for different kinds of species used in the experiment.

关键词： Band saw. Cutting speed. Profile curve. waviness or filtered wave. Roughness curve Roughness of center line average

Evolution of appearance profile of hot-dip galvanized car-body steel sheet during deformation process

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Baosteel Technical Research 2017年第2期11卷 30-36页

作者： ZHAO Yanliang SHI Jinzhong DAI Yigang Research Institute Baoshan Iron & Steel Co.Ltd. R & D Center of Great Wall Motor Company Automotive Engineering Technical Center of Hebei

In recent years, the waterborne free intermediate coating process has been widely used in the automotive industry. Because the baking times and coating thickness are decreased, the surface covering capability of the painting process is reduced, which directly affects the appearance quality（ long-and short-wave values） of the body paint. Thus, there are correspondingly higher requirements for the white body surface profile prior to painting. The surface profile of the white body is mainly affected by the plate material, the surface profile, and the deformation process. So,the change rule for the surface profile during deformation of the steel plate is a key factor in coating appearance optimization. In this paper, we first analyze the typical deformation of the outer cover of a car body. Then ,we examine the change tendency of the surface profile of steel plates with respect to different deformation rates, specifically for a steel plate comprising a hot-dip galvanized bake-hardened steel sheet. Based on our analysis of the influence of the deformation on the coating appearance,we selected 3% ,5% ,and 8% deformation rates in this research. We found the roughness （Ra） value in the typical deformation range （3% -8% ） of the car body to exhibit a decreasing trend at first and then an increasing trend. The Ra value of the 8% deformation is not more than the original plate test value. When the Pc value of the original plate is in the lower range （ about 60）, it exhibits a slight increasing trend in the deformation process （3 % -8 % ）. And when the Pc value of the original plate is in the higher range （ about 120 ）, it exhibits no increasing trend in the deformation process （ 3% -8% ）. In contrast,the waviness （WCA） value in the car body＇s typical deformation range （3%-8%） shows a significant growth trend.

关键词： automotive coating hot-dip galvanized steel sheet bake hardened steel deformation roughness waviness

Surface Roughness Quality and Dimensional Accuracy—A Comprehensive Analysis of 100% Infill Printed Parts Fabricated by a Personal/Desktop Cost-Effective FDM 3D Printer

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Materials Sciences and Applications 2018年第1期9卷 11-40页

作者： Mohammad S. Alsoufi Abdulrhman E. Elsayed Department of Mechanical Engineering College of Engineering and Islamic Architecture Umm Al-Qura University Makkah KSA

Fused deposition modeling (FDM) has become widely used for personal/ desktop cost-effective printers. This work presents an investigational platform, which is used to study the surface roughness quality, and dimensional accuracy of 100% infill density printed parts fabricated by a personal/desktop cost-effective FDM 3D printer using different types of thermoplastic filament materials namely, PLA, PLA+, ABS and ABS+. Varieties of experiments were conducted after the fabricated parts were naturally cooled down for at least three hours to room temperature. During printing work, the nozzle diameter, layer height, nozzle temperature and printing speed were set at 0.3 mm, 0.1 mm, 220°C and 30 mm/s, respectively. According to the experimentally obtained data results over 10 mm scanned profile and 90°measuring direction (perpendicular to building direction), PLA+ thermoplastic filament material shows an excellent surface behaviour and is found to be more accurate while ABS does exhibit high surface roughness, waviness and primary behaviour. Both PLA and ABS+ show good surface performance.

关键词： Additive Manufacturing (AM) Surface Roughness waviness Primary 3D Prints Fused Deposition Modeling (FDM)

A METHOD OF DISCRIMINATING THE SURFACE WAVE VISIBILITY

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Chinese Science Bulletin 1988年第23期33卷 1933-1936页

作者：于光薛秉源 Shanghai Jiaotong University

Ⅰ. INTRODUCTION In practical production and scientific research, whether the surface waviness is good is often judged by the surface wave visibility (SWV) with human eyes. Since this method is affected by the subjective of the operator, sometimes it is inexact. Moreover, it may lead up to a wrong conclusion because there is no direct relationship between the SWV and the wave amplitude. On the other hand, the SWV usually affects the appearance of a machined workpiece. Therefore, it is necessary to find a new method which can discriminate the SWV objectively.

关键词： pattern coefficient surface wave visibility waviness grinding