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characteristic of Torsional vibration of Mill Main Drive Excited by Electromechanical Coupling

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 180-187页

作者： ZHANG Yifang YAN Xiaoqiang LIN Qihui Institute of Mechanical Engineering University of Science and Technology Beijing School of Mechanical Engineering Anhui University of Technology

In the study of electromechanical coupling vibration of mill main drive system, the influence of electrical system on the mechanical transmission is considered generally, however the research for the mechanism of electromechanical interaction is lacked. In order to research the electromechanical coupling resonance of main drive system on the F3 mill in a plant, the cycloconverter and synchronous motor are modeled and simulated by the MTLAB/SIMUL1NK firstly, simulation result show that the current harmonic of the cycloconverter can lead to the pulsating torque of motor output. Then the natural characteristics of the mechanical drive system are calculated by ANSYS, the result show that the modal frequency contains the component which is close to the coupling vibration frequency of 42Hz. According to the simulation result of the mechanical and electrical system, the closed loop feedback model including the two systems are built, and the mechanism analysis of electromechanical coupling presents that there is the interaction between the current harmonic of electrical system and the speed of the mechanical drive system. At last, by building and computing the equivalent nonlinear dynamics model of the mechanical drive system, the dynamic characteristics of system changing with the stiffness, damping coefficient and the electromagnetic torque are obtained. Such electromechanical interaction process is suggested to consider in research of mill vibration, which can induce strong coupling vibration behavior in the rolling mill drive system.

关键词： rolling mill vibration current harmonic speed oscillation electromechanical coupling vibration characteristic

Research on Breeze vibration Law and Modal Identification Method of Conductor Considering Anti-vibration Hammer Damage

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Structural Durability & Health Monitoring 2023年第4期17卷 283-297页

作者： Long Zhao Xudong Lu Xinbo Huang Hao Yang Guoze Feng School of Information and Electronics Xi’an Polytechnic UniversityXi’an710048China

In the harsh environment,the structural health of the anti-vibration hammer,which suffers from the coupled effects of corrosion and fatigue damage,is significantly *** part of the conductor structure,the anti-vibration hammer is rigidly attached to the conductor,effectively suppressing conductor *** conductor’s breeze vibration law and natural modal frequency are altered damage to the anti-vibration hammer *** built a vibration experiment platform to simulate multiple faults such as anti-vibration hammer head drop off and position slippage,which to obtained the vibration acceleration signal of the *** acceleration vibration signal is processed and analyzed in the time and frequency *** results are used to derive the breeze vibration law of the conductor under multiple faults and propose an anti-vibration hammer damage online monitoring *** results show that the vibration acceleration value and vibration intensity of the conductor are significantly increased after the anti-vibration hammer *** natural frequency increases for each order,with an absolute change ranging from 0.15 to 6.49 *** anti-vibration hammer slipped due to a loose connection,the 1st natural frequency increases from 8.18 to 16.62 ***,in engineering applications,there can be no contact to determine the anti-vibration hammer damage situation by monitoring the modal natural frequency of the *** is even a tiny damage that cannot be *** method will prevent the further expansion of the damage that can cause accidents.

关键词： Transmission line conductor anti-vibration hammer breeze vibration modal parameter vibration characteristic

MATHEMATICAL ANALYSIS OF TRANSVERSE vibration OF CONICAL SPIRAL TUBE BUNDLE WITH EXTERNAL FLUID FLOW

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维普期刊数据库

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Journal of Hydrodynamics 2010年第6期22卷 816-822页

作者： YAN Ke GE Pei-qi SU Yan-cai BI Wen-bo Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of Education School ofMechanical Engineering Shandong University Jinan 250061 China

The conical spiral tube bundle is a new type of heat transfer elements used to enhance heat transfer through flow-induced vibration. The effect of the external fluid flow on the transverse vibration of the conical spiral tube bundle is investigated with a mathematical method proposed in this article. Firstly, the natural vibration of the tube bundle is obtained by the hammering excitation method and the mode shapes of the transverse vibration are discussed. Then the effect of the external fluid flow on the transverse vibration of tube bundle is analyzed by a combination of experimental data, empirical correlations and FEM. The results show that in the frequency range from 0 Hz to 50 Hz, there exist six transverse vibrations. The external fluid flow has a significant effect on the frequency of the tube＇s transverse vibration, which are decreased by about 18% to 24% when the external fluid flow speed is 0.3 m/s.

关键词： conical spiral tube bundle mathematical model vibration characteristic FEM

A ring type standing wave ultrasonic motor using cantilever type longitudinal transducers

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Journal of Harbin Institute of Technology(New Series) 2011年第1期18卷 52-56页

作者：刘英想刘军考陈维山石胜君 State Key Laboratory of Robotics and System Harbin Institute of Technology

The disadvantages of classic ring type ultrasonic motor were *** obtain large mechanical output power,a ring type standing wave ultrasonic motor using cantilever type longitudinal transducers was *** are four pairs of cantilevers on one side of the ring,and four PZT ceramics are set between each pair of cantilevers.A screw fastened the PZT ceramics and cantilevers together to form a longitudinal *** bending vibration mode of the ring is excited by the stretching vibration of the PZT ***,linear simple harmonic motions are achieved at the particle on the *** the driving force is the frictional force between rotor and *** working principle of the proposed motor was *** ring and the longitudinal transducer were designed with *** sensitive parameters of resonant frequency of the transducer and ring could be gained with modal *** longitudinal vibration modal of transducer and bending vibration modal of ring were degenerated,and the motion trajectories of nodes on the teeth were *** results of this paper could guide the development of this new type of motor.

关键词： ultrasonic motor standing wave ring type vibration characteristic FEM

Optimization Method of Bearing Support Positions in a High-Speed Flexible Rotor System

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Journal of Donghua University(English Edition) 2020年第6期37卷 504-511页

作者：唐昌柯姜艳红刘静 College of Mechanical Engineering Chongqing UniversityChongqing 400044China High-Speed Railway Bearing Co. Ltd.Zhejiang 324000China School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China

Bearing support position is one of main factors affecting vibration characteristics of rotor systems. To optimize the bearing support positions in a high-speed flexible rotor system (HSFRS) based on the vibration characteristics, an optimization method of bearing support positions in the HSFRS is proposed. In this method, a finite element (FE) model of a high-speed flexible rotor (HSFR) was established. The natural frequencies and mode shapes of the HSFRS were used to obtain the initial design scheme of the bearing support positions. A frequency characteristic equation of the HSFRS was established to obtain the critical speeds of the HSFRS. And a dynamic model of the HSFRS was established to analyze the vibration characteristics for different bearing support position cases. The problem of optimizing bearing support positions in the HSFRS was solved by the developed method. The results showed that vibration amplitudes of the HSFRS were more stable when the bearing support positions were optimized. This study can provide a new method for optimizing bearing support positions of rotor systems.

关键词： flexible rotor system optimal design vibration characteristic bearing support position

DESIGN OF A CROSS-SHAPED PIEZOELECTRIC MOTOR WITH SINGLE DRIVING FOOT

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DESIGN OF A CROSS-SHAPED PIEZOELECTRIC MOTOR WITH SINGLE DRI...