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.

The Gap Nonlinear Characteristics of Gear Transmission System under External Excitation

2012 ◽  
Vol 215-216 ◽  
pp. 1067-1070
Author(s):  
Kang Huang ◽  
Jue Li ◽  
Xin Jin ◽  
Qi Chen
Keyword(s):  
Dynamic Characteristics ◽  
Nonlinear Dynamic ◽  
Degrees Of Freedom ◽  
Transmission System ◽  
Gear Transmission ◽  
Engineering Practice ◽  
Nonlinear Dynamic Model ◽  
Gear Transmission System ◽  
Nonlinear Dynamic Characteristics ◽  
Domain Of Parameters

For the study of nonlinear dynamic characteristics of a pair of gears in an external torque under gear meshing error excitation, we will establish two degrees of freedom nonlinear torsional vibration model. The use of Matlab / Simulink for numerical simulation solves the nonlinear dynamic model of the gear gap. Study the dynamic characteristics of the system in a certain domain of parameters on external incentive conditions, as well as external motivation of gear transmission system dynamic characteristics influence. The results have important practical value for future engineering practice on gear transmission system's dynamic design, and have important theoretical significance for complex gear transmission system dynamics study.

Analysis on the vibration reduction for a new rigid–flexible gear transmission system

2021 ◽  
pp. 107754632110132
Author(s):  
Zhibo Geng ◽  
Junyang Li ◽  
Ke Xiao ◽  
Jiaxu Wang
Keyword(s):  
Dynamic Model ◽  
Vibration Reduction ◽  
Surface Friction ◽  
Transmission System ◽  
Gear Transmission ◽  
Dynamic Responses ◽  
Gear Pair ◽  
Nonlinear Dynamic Model ◽  
Gear Transmission System ◽  
Flexible Gear

In this study, a new rigid–flexible gear with metal rubber is proposed to reduce the vibration of the gear transmission system. A nonlinear dynamic model with nine degrees of freedom considering bearing clearance, gear backlash, surface friction, and time-varying meshing stiffness is established. The nondimensional dynamic model of the transmission system is obtained and the bifurcation characteristics of the new rigid–flexible gear pair and the rigid gear pair are analyzed when the damping coefficient is, respectively, 0.03 and 0.1. The result shows that the motion state of the rigid–flexible gear pair is more stable. The dynamic responses of the rigid gear pair and the rigid–flexible gear pair are compared as well through numerical analysis and experiment to illustrate the advantage of the rigid–flexible gear pair in vibration reduction. The results can provide reference for vibration reduction of the novel gear transmission.

Nonlinear dynamic characteristics analysis and chaos control of a gear transmission system in a shearer under temperature effects

2019 ◽  
Vol 233 (16) ◽  
pp. 5691-5709 ◽  
Author(s):  
Jiajun Chen ◽  
Wei Li ◽  
Gaifang Xin ◽  
Lianchao Sheng ◽  
Song Jiang ◽  
...  
Keyword(s):  
Bifurcation Diagram ◽  
Dynamic Characteristics ◽  
Nonlinear Dynamic ◽  
Coupling Effect ◽  
Transmission System ◽  
Resonance Excitation ◽  
Gear Pair ◽  
Direct Drive ◽  
Nonlinear Dynamic Model ◽  
Dimensionless Analysis

Due to changes in the working temperature in a shearer transmission system, it is easy to cause the transmission gear to work abnormally. In this paper, the first gear pair in a cutting transmission system of a permanent magnet semi-direct drive shearer was taken as the research object. The coupling effect of time-varying meshing stiffness, meshing damping, bearing clearance and gear backlash under thermal deformation were fully considered. Then, a three degree of freedom nonlinear dynamic model of the gear pair was established, and a dimensionless analysis was performed. Finally, the Runge-Kutta method was used in the numerical calculations. The motion characteristics of the system were analysed through the gear’s bifurcation diagram of the temperature at different frequencies and the bifurcation diagram of the frequency at different temperatures. The meshing state was analysed at different frequencies and temperatures. For the chaotic motion generated in the system, a periodic resonance excitation was applied to control unstable motion. This study has revealed various specific effects of the temperature on the dynamic characteristics of the system. In addition, the periodic excitation method can effectively control the nonlinear motion in the system and realise the control of the chaos under the temperature effect.

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.

Effects of directional rotation radius and transmission error on the dynamic characteristics of face gear transmission system

2013 ◽  
Vol 228 (7) ◽  
pp. 1108-1118 ◽  
Author(s):  
Jinyuan Tang ◽  
Zehua Hu ◽  
Siyu Chen ◽  
Duncai Lei
Keyword(s):  
Dynamic Characteristics ◽  
Transmission Error ◽  
Transmission System ◽  
Gear Transmission ◽  
Dynamic Factor ◽  
Gear Pair ◽  
Face Gear ◽  
Amplitude Variation ◽  
Gear Transmission System ◽  
Static Transmission Error

The effects of directional rotation radius and transmission error excitation on the nonlinear dynamic characteristics of face gear transmission system are analyzed. First, the accurate time-varying mesh stiffness is calculated using finite element method, and the nonlinear motion equation of the system under static transmission error excitation is proposed. The frequency response curve, time history curve, dynamic mesh force curve and dynamic factor curve are given, and the phenomena of jump, multiple solutions and tooth impact are observed. The numerical results show that the effect of amplitude variation of directional rotation radius on the dynamic characteristics of face gear pair is less conspicuous than that of transmission error but actually existing. The amplitude of the dynamic response of face gear pair reduces to some extent with the uniform distribution of the loading area through enlarging the amplitude variation of directional rotation radius. The static transmission error excitation should be reduced to perfect the transmission property. The system is in periodic motion most of the time, and tooth impact occurs only near [Formula: see text] . Since its dynamic property at low velocity and high velocity is good, the system should get through the resonant area quickly in work.

Influence of the Random System Parameters on the Nonlinear Dynamic Characteristics of Gear Transmission System

2017 ◽  
Vol 18 (7-8) ◽  
pp. 619-630
Author(s):  
Jingyue Wang ◽  
Haotian Wang ◽  
Huan Wang ◽  
Lixin Guo
Keyword(s):  
Dynamic Characteristics ◽  
Nonlinear Dynamic ◽  
Damping Ratio ◽  
Transmission System ◽  
Gear Transmission ◽  
Random Parameters ◽  
Meshing Stiffness ◽  
Gear Backlash ◽  
Gear Transmission System ◽  
Nonlinear Dynamic Characteristics

AbstractIn order to analyze the influence of the random parameters of the system on the nonlinear dynamic characteristics of the gear transmission system, considering the random perturbation of damping ratio, gear backlash, meshing frequency, meshing stiffness and the low frequency excitation caused by torque fluctuation, the random vibration equations of three-degree-of-freedom gear transmission system are established according to the Newton’s law. The motion differential equations are solved by the Runge–Kutta method. The effects of different random parameters such as load ratio, tooth frequency ratio, damping ratio, gear backlash and meshing stiffness on the dynamic response of the gear transmission system are analyzed in light and heavy loads and low and high speeds.

scholarly journals Dynamic characteristics analysis of planetary gear system with internal and external excitation under turbulent wind load

2021 ◽  
Vol 104 (3) ◽  
pp. 003685042110356
Author(s):  
Hexu Yang ◽  
Xiaopeng Li ◽  
Jinchi Xu ◽  
Zemin Yang ◽  
Renzhen Chen
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Nonlinear Dynamic ◽  
Planetary Gear ◽  
Wind Load ◽  
Transmission System ◽  
Gear Transmission ◽  
Stiffness Ratio ◽  
Gear Transmission System ◽  
Planetary Gear System

According to the working characteristics of a 1.5 MW wind turbine planetary gear system under complex and random wind load, a two-parameter Weibull distribution model is used to describe the distribution of random wind speed, and the time-varying load caused by random wind speed is obtained. The nonlinear dynamic model of planetary gear transmission system is established by using the lumped parameter method, and the relative relations among various components are derived by using Lagrange method. Then, the relative relationship between the components is solved by Runge Kutta method. Considering the influence of random load and stiffness ratio on the planetary gear transmission system, the nonlinear dynamic response of cyclic load and random wind load on the transmission system is analyzed. The analysis results show that the variation of the stiffness ratio makes the planetary gear have abundant nonlinear dynamics behavior and the planetary gear can get rid of chaos and enter into stable periodic motion by changing the stiffness ratio properly on the premise of ensuring transmission efficiency. For the variable pitch wind turbine, the random change of external load increases the instability of the system.

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