Nonlinear Dynamic Characteristics of Wind Turbine Gear System Caused by Tooth Crack Fault

2021 ◽  
Vol 31 (10) ◽  
pp. 2150148
Author(s):  
Ling Xiang ◽  
Chaohui An ◽  
Aijun Hu
Keyword(s):  
Wind Turbine ◽  
Nonlinear Dynamic ◽  
Gear System ◽  
System Response ◽  
Normal System ◽  
Dynamic Features ◽  
Nonlinear Dynamic Model ◽  
Mesh Stiffness ◽  
Potential Energy Method ◽  
Root Crack

Crack in gears impacts the dynamic response of wind turbine multistage gear system, which also influences the safe operation of wind turbine. A translational–torsional nonlinear dynamic model of the multistage gear system is proposed with root crack fault. The model considers the effects of sun gear support, time-varying mesh stiffness, gear backlash and other factors. The mesh stiffness with root crack is analyzed by using potential energy method. Based on the Runge–Kutta method, the system responses are obtained with multiple parameters changing. The nonlinear dynamic features of the cracked and normal system are compared by bifurcation diagram, time series, phase trajectory, Poincaré map, spectrum diagram and corresponding three-dimensional diagrams. The analyses show the effects of input torque, backlash, crack occurrence and evolution on the system dynamic behaviors, and the effect of crack fault on the gear system response is further verified by experiment. The results provide a theoretical basis for the cognition of fault mechanism and fault diagnosis of wind turbine gearbox.

Nonlinear Dynamics Analysis of Gear System Considering Unbalance and Loosening Faults

2014 ◽  
Vol 875-877 ◽  
pp. 1976-1981 ◽  
Author(s):  
Li Cui ◽  
Da Fang Shi ◽  
Jian Rong Zheng ◽  
Xiao Guang Song
Keyword(s):  
Nonlinear Dynamic ◽  
Gear System ◽  
Dynamic Equations ◽  
Radial Clearance ◽  
Nonlinear Dynamic Model ◽  
Mesh Stiffness ◽  
Diverse Range ◽  
Runge Kutta Method ◽  
Nonlinear Dynamic Equations ◽  
Chaos Motion

Considering backlash, radial clearance of bearing and time-varying mesh stiffness, nonlinear dynamic model of gear bearing rotor system is established considering unbalance and loosening fault. Nonlinear dynamic equations are solved using Runge-Kutta method and Newton-Raphson method. Numerical simulations of the dynamic equations and the affection of the depth of crack and length of wear to the nonlinear dynamic behavior are studied. The results shows that tooth off, bilateral impact phenomenon are occurred, with increasing gear failure when unbalance occurs, and the gear system exhibits a diverse range of periodic, quasi-periodic and chaotic motion. When loosening fault occurs, the range of chaos motion is increased, and gear burnishing is also intensified.

Dynamic Response Analysis of Wind Turbine Planetary Gear System With Interval Stiffness Parameters

2014 ◽  
Author(s):  
Sha Wei ◽  
Qinkai Han ◽  
Zhipeng Feng ◽  
Yanhua Shen ◽  
Fulei Chu
Keyword(s):  
Wind Turbine ◽  
Planetary Gear ◽  
Transmission Error ◽  
Gear System ◽  
Dynamic Responses ◽  
Lumped Parameter Model ◽  
Response Analysis ◽  
Mesh Stiffness ◽  
Gear Trains ◽  
Planetary Gear System

Planetary gear transmission system is one of the primary parts of the wind turbine drive train. Due to the assembly state, lubrication conditions and wear, the mesh stiffness of the planetary gear system is an uncertain parameter. In this paper, taking the uncertainty of mesh stiffness into account, the dynamic responses of a wind turbine gear system subjected to wind loads and transmission error excitations are studied. Firstly, a lumped-parameter model is extended to include both the planetary and parallel gears. Then the fluctuation ranges of dynamic mesh forces are predicted quantitatively and intuitively based on the combined Chebyshev interval inclusion function and numerical integration method. Finally, examples of gear trains with different interval mesh stiffnesses are simulated and the results show that tooth separations are becoming more obvious at the resonant speed by considering the fluctuating mesh stiffness of the second parallel gear stage. The nonlinear tooth separations are degenerated obviously as the fluctuation error of the mesh stiffness of the second parallel gear set is increased.

Nonlinear dynamic analysis of spur gear system based on fractional-order calculus

2020 ◽  
Vol 34 (36) ◽  
pp. 2050420
Author(s):  
Jingyu Hou ◽  
Shaopu Yang ◽  
Qiang Li ◽  
Yongqiang Liu
Keyword(s):  
Fractional Order ◽  
Nonlinear Dynamic ◽  
Numerical Solutions ◽  
Nonlinear Dynamic Analysis ◽  
Harmonic Balance Method ◽  
Spur Gear ◽  
Nonlinear Dynamic Model ◽  
Mesh Stiffness ◽  
Incremental Harmonic Balance Method ◽  
Internal Excitation

In this paper, nonlinear dynamic model of spur gear pairs with fractional-order damping under the condition of time-varying stiffness, backlash and static transmission error is established. The general formula of fractional-order damping term is derived by using the incremental harmonic balance method (IHBM), and the approximate analytical solution of the system is obtained by use of the iterative formula. The correctness of the results is verified by comparing with the numerical solutions in the existing literature. The effects of mesh stiffness, internal excitation amplitude and fractional order on the dynamic behavior of the system are analyzed. The results show that changing the fractional order can effectively control the resonance position and amplitude in the meshing process. Both the mesh stiffness and internal excitation can control the collision state and the stability.

Dynamic Features of Gear System With Tooth Crack and Tooth Surface Sliding due to Speed Variation

2012 ◽  
Author(s):  
Liming Wang ◽  
Zaigang Chen ◽  
Yimin Shao ◽  
Xi Wang
Keyword(s):  
Degrees Of Freedom ◽  
Surface Friction ◽  
Element Model ◽  
Spur Gear ◽  
Gear System ◽  
Tooth Surface ◽  
Dynamic Features ◽  
Mesh Stiffness ◽  
Speed Variation ◽  
Gear Mesh

It was found that the vibration features resulted from tooth crack and sliding on the contact interfaces due to speed variation are very similar with each other, which is difficult to distinguish. So, it is meaningful to study whether they are the same or not. Firstly, a finite element model of a spur gear pair in mesh with tooth crack at pitch circle is established to calculate the effect of tooth crack on gear mesh stiffness. Then, combined with the tooth crack through mesh stiffness, a spur gear dynamic model with six degrees of freedom (dof) is developed to extract the dynamic features affected by the tooth crack. The tooth surface friction due to different relative velocity is also involved to study its effects on the dynamic characteristics of the gear system. Finally, comparisons are made between the dynamic features of the gear system with tooth crack and the tooth surface sliding to expose their effects to supply some theoretical guidance on fault detection.

scholarly journals Dynamic Analysis of a Fault Planetary Gear System under Nonlinear Parameter Excitation

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Jianchao Han ◽  
Yinghui Liu ◽  
Lei Liang ◽  
Yang Zhao ◽  
Huibo Zhang
Keyword(s):  
Equations Of Motion ◽  
Excitation Frequency ◽  
Global Bifurcation ◽  
Planetary Gear ◽  
Gear System ◽  
Fault System ◽  
Nonlinear Dynamic Model ◽  
Motion State ◽  
Planetary Gear System ◽  
Potential Energy Method

In order to facilitate lubrication and avoid the gear stuck due to thermal expansion, there needs to be a gap between the tooth profiles. As a strong nonlinear factor, the backlash will affect the motion state of the planetary gear system. When the gear failures occur, the motion state of the system will accordingly change. In this study, the meshing stiffness of the gear pair with tooth tip chipping fault is calculated by combining the analytic geometry method and the potential energy method. Then, a new nonlinear dynamic model including tooth backlash, time-varying mesh stiffness, and manufacturing error is established to study the dynamic response of the system. The equations of motion are derived by the Lagrangian method and solved by the numerical integration method. Taking the excitation frequency and tooth backlash as the variation parameters, respectively, the dynamic characteristics of the system are analyzed by comparing the global bifurcation diagrams between the health system and the fault system, and the path of the system into chaos is revealed. At the same time, the local characteristics of the system are revealed through the phase diagrams and Poincaré maps. The results show that with the variation of excitation frequency and tooth backlash, the fault system presents a more complex motion state. This study can provide the theoretical support for dynamic design and fault diagnosis of planetary gear transmission systems under the environment of gear fault-prone.

Non-probabilistic interval process method for analyzing two-stage straight bevel gear system with uncertain time-varying parameters

2020 ◽  
pp. 095440622096769
Author(s):  
Wassim Lafi ◽  
Fathi Djemal ◽  
Dhouha Tounsi ◽  
Ali Akrout ◽  
Lassaad Walha ◽  
...  
Keyword(s):  
Bevel Gear ◽  
Gear System ◽  
Uncertain Parameters ◽  
Time Varying ◽  
Mesh Stiffness ◽  
Time Step ◽  
Two Stage ◽  
Straight Bevel Gear ◽  
Potential Energy Method ◽  
Process Method

A two-stage straight bevel gear system is a gear system that can be used in various applications. The straight bevel gear is known for its complex tooth geometry. Due to the variation of the number of pairs of teeth in contact, the mesh stiffness function can be considered as a time-varying function. However, the mesh stiffness for the straight bevel gear is sensitive to measurement and modeling errors. Thus, at each time step, its value can not assigned to deterministic one. Generally, the uncertain parameters are assumed to be time-independent. In this paper, the interval process method has been used to represent the time-varying uncertain parameters, whose bounds are determined through the potential energy method. The lumped parameter model of two-stage straight bevel gear has been proposed. We have considered that the masses of the straight bevel gear system components and bearing stiffnesses along with time-varying mesh stiffnesses are uncertain parameters which can be represented by the interval process model. The Chebyshev polynomial expansion has been used to approximate the response of the two-stage straight bevel gear system with respect to the interval variables. The lower and higher bounds of the eigenvalues of the system have been determined. The bounds of dynamic displacements of the straight bevel gear system have been computed and compared with those computed by the Monte Carlo method.

Dynamic Features of a Planetary Gear System With Tooth Crack Under Different Sizes and Inclination Angles

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
Zaigang Chen ◽  
Yimin Shao
Keyword(s):  
Planetary Gear ◽  
Gear System ◽  
Dynamic Responses ◽  
Tooth Root ◽  
Dynamic Features ◽  
Planetary Gears ◽  
Inclination Angles ◽  
Planet Gear ◽  
Planetary Gear System ◽  
Root Crack

Planetary gears are widely used in the industry due to their advantages of compactness, high power-to-weight ratios, high efficiency, and so on. However, planetary gears such as that in wind turbine transmissions always operate under dynamic conditions with internal and external load fluctuations, which accelerate the occurrence of gear failures, such as tooth crack, pitting, spalling, wear, scoring, scuffing, etc. As one of these failure modes, gear tooth crack at the tooth root due to tooth bending fatigue or excessive load is investigated; how it influences the dynamic features of planetary gear system is studied. The applied tooth root crack model can simulate the propagation process of the crack along tooth width and crack depth. With this approach, the mesh stiffness of gear pairs in mesh is obtained and incorporated into a planetary gear dynamic model to investigate the effects of the tooth root crack on the planetary gear dynamic responses. Tooth root cracks on the sun gear and on the planet gear are considered, respectively, with different crack sizes and inclination angles. Finally, analysis regarding the influence of tooth root crack on the dynamic responses of the planetary gear system is performed in time and frequency domains, respectively. Moreover, the differences in the dynamic features of the planetary gear between the cases that tooth root crack on the sun gear and on the planet gear are found.

Analysis of Tourism Ecology Capacity Based on the Nonlinear Dynamic Model

2009 ◽  
Vol 11 (2) ◽  
pp. 163-168
Author(s):  
Long LV ◽  
Zhenfang HUANG ◽  
Jiang WU
Keyword(s):  
Dynamic Model ◽  
Nonlinear Dynamic ◽  
Nonlinear Dynamic Model
Sign in / Sign up

Export Citation Format

Share Document