Erratum: “Response Sensitivity and Its Assessment of Nonlinear Vibration Using Lateral–Torsional Coupling Model of Vehicle Transmission System” [Journal of Vibration Acoustics, 2015, 137(3), p. 031013; DOI: 10.1115/1.4029416]

2015 ◽  
Vol 137 (6) ◽  
Author(s):  
C. L. Xiang ◽  
Y. Huang ◽  
H. Liu
Keyword(s):  
Nonlinear Vibration ◽  
Coupling Model ◽  
Transmission System ◽  
Response Sensitivity ◽  
Torsional Coupling

A new torsional vibration coupling model for transmission system in diesel generator

2021 ◽  
pp. 146808742110689
Author(s):  
Bin Chen ◽  
Yunbo Hu ◽  
Yibin Guo ◽  
Zhijun Shuai ◽  
Chongpei Liu ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Torsional Vibration ◽  
Coupling Model ◽  
Transmission System ◽  
System Matrix ◽  
Diesel Generator ◽  
Lumped Mass ◽  
Proposed Model ◽  
Torsional Coupling ◽  
Vibration Coupling

The coupling between the crankshaft and the camshaft is neglected before in fault diagnosis which may lead to incomplete fault information. In this paper, a new torsional coupling model of a diesel generator transmission system is proposed for fault diagnosis. The natural frequency and forced torsional vibration response of the model are obtained by the system matrix method and Newmark-β method. For the system without considering the lumped mass of camshafts, some key natural frequencies are lost. The vibration dynamics are compared for the transmission system with and without the new coupling model. And important frequency responses are missed in the spectrums of the forced torsional vibration without the new coupling model. Finally, the new coupling model is implemented in fault diagnosis and the cause of an unusual vibration fault is deduced in the simulation, which confirms the feasibility of the proposed model in fault diagnosis.

Response Sensitivity and the Assessment of Nonlinear Vibration Using a Nonlinear Lateral–Torsional Coupling Model of Vehicle Transmission System

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Chang L. Xiang ◽  
Yi Huang ◽  
Hui Liu
Keyword(s):  
Model Updating ◽  
Direct Method ◽  
Transmission System ◽  
Torsional Stiffness ◽  
Differential Sensitivity ◽  
Design Stage ◽  
Partial Amplitude ◽  
Response Sensitivity ◽  
Mass Eccentricity ◽  
Torsional Coupling

The eigensensitivity analysis does not meet the increasing industrial requirements of the dynamic performance of a vehicle transmission system. To reduce vibration, it is necessary to include response sensitivity in the guideline in the design stage. In this study, we developed a nonlinear lateral–torsional coupling spur gear system model considering the effect of time-varying mesh stiffness, clearance, mass eccentricity, and transmission error. Then the dynamic response sensitivity to system parameters was systematically analyzed by taking the shaft torsional stiffness, for example. The equation of response sensitivity was deduced by a direct method (DM) based on the fitting of the clearance function curve using a polynomial function. In allusion to the characteristic of the aperiodicity of response sensitivity curves of the nonlinear system in the time domain, a novel assessment method—differential sensitivity based on the root mean square (RMS) of response is proposed. This method provides statistical results in a certain range, thus avoiding the inaccuracy of the partial amplitude. The vibrational energy of modified system (MS) can also be estimated. All the abovementioned characteristics make it possible to provide the theoretical support for dynamic modification, model updating, and optimal design.

Integrated Design of Airborne Radar Servo System Based on MATLAB/SIMULINK

2011 ◽  
Vol 204-210 ◽  
pp. 17-20
Author(s):  
Ding Zhen Li ◽  
Rui Min Jin
Keyword(s):  
Optimization Model ◽  
Electromechanical Coupling ◽  
Integrated Design ◽  
Control Design ◽  
Servo System ◽  
Coupling Model ◽  
Transmission System ◽  
Airborne Radar ◽  
Matlab Simulink ◽  
And Control

This thesis is according to the pitching part of airborne radar servo system. The electromechanical coupling model and optimization model which includes structure parameters and control parameters are built up based on model of mechanism transmission system and electricity control system. The dynamics model of mechanism transmission system includes the nonlinearity of backlash and is considered the influence of parameters for dynamics properties in structure of the mechanism transmission system. The method of integrated structure and control design is applied on the optimization model using GA. Simulation is done based on MATLAB/SIMULINK. Simulation results show that the method of integrated structure and control design is feasible and effective in servo system.

scholarly journals Study on Fatigue Degradation Behavior of a Cracked Rotor Subjected to Lateral Vibration

2018 ◽  
Vol 2018 ◽  
pp. 1-21 ◽  
Author(s):  
Qian Niu ◽  
Shi-xi Yang
Keyword(s):  
Nonlinear Vibration ◽  
Crack Growth ◽  
Coupling Effect ◽  
Coupling Model ◽  
Degradation Behavior ◽  
Cracked Rotor ◽  
Multiple Parameters ◽  
Degradation Failure ◽  
Degradation Behaviors ◽  
Unstable Vibration

Fatigue crack in a rotary shaft is a common failure observed in rotor systems. Since vibration of the shaft causes alternating fatigue loads, the crack propagates slowly. Meanwhile, the propagating crack may cause nonlinear or unstable vibration of the rotor system. In fact, growth of the crack and vibration of the shaft are coupled with each other. Hence, it is necessary to study the fatigue degradation behavior of the cracked rotor accounting for this coupling effect. In this paper, a coupling model of rotor vibration and crack growth is established through dynamic theory and fracture mechanics, and a sequential iterative procedure is proposed to solve the coupling model. Then, the competing degradation failure mode of the cracked rotor is analyzed with regard to the rapid crack growth failure and the unstable vibration failure. And degradation measures are proposed based on the competing degradation failure criterion. At last, degradation behaviors with the coupling effect of nonlinear vibration behavior and multiple parameters including rotation speed, unbalance eccentricity and orientation angle, and damping are investigated by numerical simulation. The results indicate that nonlinear vibration behavior and multiple parameters have considerable influence on the degradation behaviors, which present complex regularity. The findings are of significance to guide the safety design of the rotor system for long time operation and help to the further research on prognostics and lifetime prediction.

scholarly journals Effects of Transmission Ratio on the Nonlinear Vibration Characteristics of a Gear-Driven High-Speed Centrifugal Pump

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Anmin Zhou ◽  
Lulu Zhai ◽  
Zuchao Zhu ◽  
Jia Guo ◽  
Xinglin Zhang ◽  
...  
Keyword(s):  
Nonlinear Vibration ◽  
Centrifugal Pump ◽  
High Speed ◽  
Transmission System ◽  
Gear Transmission ◽  
Transmission Ratio ◽  
Gear Pair ◽  
Motion State ◽  
Vibration Responses ◽  
The Stability

The gear transmission system is widely used in high-speed centrifugal pump to improve the operating speed and hydraulic performances of the whole pump. Vibration characteristics and the stability of these high-speed rotor systems with gear transmission have great impacts on the stability of the whole fluid transmission system of the plant. Based on the lumped-mass method and the principle of displacement equilibrium of the rotor system, a coupled lateral-torsional dynamic model describing the gear-rotor-seal-bearing (GRSB) system of high-speed centrifugal pumps which has considered the nonlinear factors within the gear pair, nonlinear forces of bearings, and those of the seals is proposed. Then, the stability and nonlinear vibration responses of a model GRSB system under different gear transmission ratios (i) have been studied. The following conclusions are drawn from the results: (1) The components with frequencies like fp, f g , fm, and 2fm have great impacts on the vibration responses of the gear pair, especially the fm component; moreover, the amplitude of fm first increases and then decreases with the ratio increase and reaches the maximum value under the ratio of 3. (2) A jump motion state will occur when the ratio i is 1.25 and the stability of the system is obviously worse than the bifurcation state. Quite different from those under the other states, under this jump motion state, the 0.2 f g component and 0.5fp component will appear in the vibration responses of both gears and become the most contributed two factors to the responses of the driven gear. (3) In the design process, the transmission ratio of a high-speed centrifugal pump with a simplified GRSB system should be specially designed to avoid the jump-point state and the maximum-amplitude-of-fm state to ensure the stability of the system as well as reduce the mechanical impacts and noises.

scholarly journals Influence of electrical part of traction transmission on dynamic characteristics of railway vehicles based on electromechanical coupling model

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xun Wang ◽  
Tiefeng Peng ◽  
Pingbo Wu ◽  
Litong Cui
Keyword(s):  
High Speed ◽  
Electromechanical Coupling ◽  
Low Frequency ◽  
Traction Force ◽  
Coupling Model ◽  
Transmission System ◽  
Transmission Model ◽  
Rail Transit ◽  
Mechanical Coupling ◽  
Car Body

AbstractWith the continuous development of rail transit industry and the acceleration of train speed, higher requirements are established for the operation quality of high-speed trains and the reliability of transmission system. In the process of train running, speed fluctuation and vibrations from various parts of the driving devices are common, which could be greatly affected by the traction torque. During traction transmission, the harmonic vibration torque exists in traction motor due to that the motor is connected with non-sinusoidal alternating current. In order to study the vibration influence of the electrical component of traction transmission system on the rail vehicles, i.e., bogie and car-body, an electro-mechanical coupling dynamic model for rail transit vehicles was established by explicitly incorporating the electric-induced traction into the transmission model. The dynamics responses of the vertical, lateral and longitudinal acceleration on vehicle components, such as axle box and car-body were quantitative analyzed. By comparison with field test, it was observed that there was a vibration peak of 12-times of the fundamental rotor frequency on the bogie frame and axle box, which existed at conditions of traction, uniform speed and braking. However, the vibration acceleration exhibit nearly little difference with or without traction force, especially at low frequency domain < 100 Hz.

Nonlinear Dynamic Analysis of a Rigid–Flexible Gear Transmission Considering Geometric Eccentricities

2020 ◽  
Vol 15 (8) ◽  
Author(s):  
Zhibo Geng ◽  
Ke Xiao ◽  
Jiaxu Wang ◽  
Junyang Li
Keyword(s):  
Nonlinear Vibration ◽  
Dynamic Characteristics ◽  
Nonlinear Dynamic ◽  
Nonlinear Dynamic Analysis ◽  
Transmission System ◽  
Operating Conditions ◽  
Gear Transmission ◽  
Gear Pair ◽  
Wide Range ◽  
Flexible Gear

Abstract Nonlinear vibration, a main factor affecting the dynamic stability, widely exists in the transmission system. In addition, geometric eccentricities caused by the manufacturing errors are inevitable in the gear transmission system, which may lead to the excessive nonlinear vibration. In order to suppress the nonlinear vibration under the excitation of the geometric eccentricities, a rigid–flexible gear pair consisting of the ring gear, the composite material, and the hub is proposed in this study. A dynamic model with nine degrees-of-freedom which considers geometric eccentricities is proposed to analyze the nonlinear dynamic characteristics of the rigid–flexible gear pair. Furthermore, the dynamic characteristics of the rigid–flexible gear pair and the rigid gear pair are compared within a wide range of operating conditions. The comparative analysis demonstrates that the rigid–flexible gear pair has better vibration suppression effect on the system.

scholarly journals Analysis of the characteristics of electromechanical-hydraulic model of multi-source drive/transmission system based on periodic excitation

2019 ◽  
Vol 11 (1) ◽  
pp. 168781401881712
Author(s):  
Yang Yang ◽  
Yuquan Mi ◽  
Datong Qin ◽  
Aihui Yuan ◽  
Guowei Li
Keyword(s):  
Dynamic Characteristics ◽  
Coupling Model ◽  
Flow Speed ◽  
Transmission System ◽  
Drive System ◽  
Lumped Parameter Model ◽  
Time Varying ◽  
Flow Pulsation ◽  
Meshing Stiffness ◽  
Internal Excitation

Multi-source drive system with the feature of compact, small size and other advantages is widely used in large engineering machinery, such as shield machine, wind turbines, and shearer. In this article, a reasonable power transmission form is designed and the electromechanical-hydraulic coupling model of the multi-source drive system including the hydraulic pump-motor lumped parameter model and gear system dynamics model is established based on the co-simulation of MATLAB and AMEsim. Taking the pump flow pulsation and the time-varying meshing stiffness as the external and internal excitation of the multi-source drive system, respectively, the vibration and the dynamic characteristics of the multi-source drive system and the transfer characteristics of the dynamic excitation are analyzed. Results show that the flow-speed pulsation and the pressure-torque pulsation are gradually reduced along the direction of the transmission chain. As the external and internal excitation, the flow pulsation and the time-varying meshing stiffness will cause complex influences on the vibration and the dynamic characteristics of the multi-source transmission system. The findings provide a reference basis for the design of the multi-source drive system.

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