考虑随机制造误差的风力机行星齿轮系统动力学特性

为研究综合传递误差的随机波动对风力发电机齿轮传动系统动力学特性的影响,考虑齿轮时变啮合刚度、综合传递误差等因素,建立风力发电机行星齿轮传动系统纯扭转动力学模型。以随机风速引起的齿轮系统转矩波动作为行星齿轮系统的外部激励,对某1.5 MW风力发电机行星齿轮传动系统的动力学特性进行仿真分析,得到系统各响应量时域内的统计特征和齿轮副间的动态啮合力统计特征。分析表明：行星架、行星轮和太阳轮在扭转方向上的振动特性与外部载荷相关,其振动位移与外部载荷波动有相似变化的趋势;综合传递误差随机分量的离散程度对行星齿轮系统的动态特性和齿轮副间的动态啮合力有较大影响。随着综合传递误差随机分量离散程度的增加,行星架、太阳轮和行星轮在扭转方向上的振动幅值明显增加;综合传递误差随机分量的随机性使齿轮副间动态啮合力产生随机波动,随机分量离散程度越大,动态啮合力波动越明显;当随机分量的离散程度达到某一值时,齿轮啮合过程发生脱离,引发啮合冲击。     

考虑多轴柔性的人字行星齿轮传动系统动态特性研究

基于有限单元法,建立了一种全自由度人字行星齿轮传动系统动力学模型.模型将时变啮合刚度、综合啮合误差和啮合相位作为动态激励,分析了太阳轮轴柔性和行星轮轴柔性对人字行星齿轮传动系统中内外啮合动态啮合力和动态传递误差的影响.结果表明:轴的柔性变形对人字齿轮行星传动系统的动态特性具有显著影响,考虑轴柔性后,人字齿轮左右两侧斜齿...     

摩擦系数对直齿轮副振动特性的影响

滑动摩擦是齿轮啮合过程中不可忽视的激励源。瞬时振动速度影响啮合齿的相对滑动速度,导致摩擦力的变化,从而可能增加齿轮振动。采用集中参数法,综合考虑时变啮合刚度、静态传递误差、内外部激励、支撑刚度、弯曲刚度及阻尼等因素的影响,建立了考虑时变摩擦系数的直齿轮副的集中参数模型,并通过数值分析方法求解系统运动微分方程,分析齿轮系统振动响应特性。研究结果表明,在不同工况条件下,滑动摩擦力对动态啮合力和动态传递误差的周期产生轻微影响,并在幅值处产生明显变化。选择合适的工况与降低齿面摩擦对齿轮系统疲劳寿命和减振降噪具有重要意义。     

基于动力学的风力发电机齿轮传动系统模糊可靠性评估

针对风力发电机齿轮传动系统在变风速工况下失效率高的问题,在模拟真实风速的基础上,建立考虑外部随机风载及内部轮齿时变啮合刚度、轴承时变刚度及综合传递误差等激励因素的风力发电机齿轮传动系统齿轮)轴承耦合动力学模型,通过对动力学模型进行仿真计算,得到各齿轮副的动态啮合力和各支承轴承的动态接触力。在此基础上,利用有限单元法、赫兹接触理论和数理统计理论得到了传动系统各齿轮和各支承轴承的动态接触力的概率分布,基于应力)强度干涉理论建立风力发电机齿轮传动系统关键零部件的模糊可靠性模型,并计算了关键零部件及系统的模糊可靠度。     

船用齿轮箱动响应的有限元分析与计算

采用MASTA软件与ANSYS软件相结合的方法,对箱体进行子结构分析,利用凝聚节点实现了传动系统和箱体的耦合连接,建立了大功率船用齿轮箱系统的动力学分析耦合模型。在对齿轮啮合刚度激励、传递误差激励和啮合冲击激励分析计算的基础上,对齿轮传动系统相啮合齿轮的动态啮合力进行了分析计算。并将该动态啮合力进行转换得到轴承处的动态力,施加在相应的凝聚节点上,对齿轮箱体的动响应进行了分析。     

基于动力学的风电增速箱多级齿轮传动系统可靠性评估

针对风力发电机齿轮传动系统在变风速工况下失效率高的问题,在模拟真实风速的基础上,建立了考虑外部随机风载及内部轮齿时变啮合刚度、轴承时变刚度、综合传递误差等激励因素的风力发电机齿轮传动系统齿轮-轴承耦合动力学模型,通过对动力学模型进行仿真计算,得到了各齿轮副的动态啮合力和各支承轴承的动态接触力,并求得齿轮的使用系数、齿轮和轴承的载荷系数。在此基础上,建立了基于动力学的风电齿轮传动系统可靠性评估模型,并求得了各零件及传动系统的可靠度,较全面地评价了随机风载作用下风力发电机齿轮传动系统的可靠性,为风力发电机齿轮传动系统可靠性设计和动态优化奠定了基础。     

随机风作用下风力发电机齿轮传动系统动载荷计算及统计分析

针对风力发电机齿轮传动系统在随机风作用下失效率高的问题,在模拟真实风速的基础上,建立考虑外部随机风载及内部齿轮时变啮合刚度、轴承时变刚度及综合传递误差等激励因素的风力发电机齿轮传动系统齿轮-轴承耦合动力学模型,通过对动力学模型进行仿真计算,得到各齿轮副的动态啮合力和各支承轴承的动态接触力。结合有限单元法和赫兹接触理论,得到关键零部件的应力时间历程,采用雨流计数法对应力时间历程进行统计分析,得到传动系统各关键零部件承受载荷的应力谱及概率分布函数。研究结果为风力发电机齿轮传动系统的动态可靠性分析和疲劳寿命预测奠定基础。     

含侧隙齿轮副的动载荷分析

以振动理论为基础，提出一种考虑齿轮拍击振动的齿轮动载荷的数值计算方法。建立计算动载荷的齿轮冲击模型，在模型中考虑了齿轮正、反冲击时实际的啮合刚度，并给出啮合柔度的计算方法。分析在考虑静态传递误差、啮合刚度、侧隙、摩擦力及外部扭矩变化等多种激励时，作用在轮齿上的动态载荷以及整个齿轮上的综合动态载荷的计算公式。最后通过实例分析作用在轮齿上的动态载荷、综合动态载荷变化规律以及相关激励参数对动态载荷的影响。     

考虑齿厚偏差的圆柱齿轮副振动特性分析

为了研究齿厚偏差对圆柱齿轮副振动特性的影响规律,建立了考虑齿厚偏差的圆柱齿轮副啮合刚度和传递误差计算模型,分析了齿厚偏差对圆柱齿轮副啮合刚度和传递误差激励的影响;然后建立了考虑齿厚偏差的圆柱齿轮啮合副有限元模型,分析了齿厚偏差对圆柱齿轮副振动特性的影响。结果表明:随着齿厚偏差增大,齿轮副单齿啮合刚度降低,传递误差和啮合振动增大;随着螺旋角减小,齿轮副单齿啮合刚度逐渐降低,传递误差波动和啮合振动增大,同时齿轮副振动特性对齿厚偏差更加敏感;随着作用扭矩减小,齿轮副单齿啮合刚度降低,传递误差激励减小,啮合振动减小,同时齿轮副振动特性对齿厚偏差敏感性降低。     

内外激励作用下地铁齿轮传动系统振动特性研究

地铁齿轮系统作为关键的传动装置,其振动特性对地铁的安全运行具有重要的影响。为研究转速、内部机理啮合误差对地铁齿轮传动系统非线性振动的影响,本文在同时考虑时变啮合刚度、时变啮合阻尼、综合传递误差、外部激励波动的基础上,建立了具有2自由度的齿轮扭转动力学模型,推导了齿轮传动系统的动力学微分方程,并运用RungeKutta数值积分法对其进行分析。本文借助于分叉图来说明齿轮传动系统在不同参数下周期、逆周期和混沌运动的变化情况,进而揭示传动系统的稳定性。研究结果表明,在较低或较高转速下,齿轮传动系统表现出简单的周期运动,进而表明转速对齿轮系统的动态特性有一定的控制作用。当内部激励啮合误差增大时,系统的逆周期和混沌运动逐渐消失,主要表现出简单的周期运动,但相应的幅值明显增大。本文的研究为地铁齿轮传动系统的减振降噪提供一定的理论基础。     

Nonlinear dynamic analysis of coupled gear-rotor-bearing system with the effect of internal and external excitations

Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out. However, the nonlinear characteristics of gear systems under combined internal and external excitations are scarcely investigated. An eight-degree-of-freedom(8-DOF) nonlinear spur gear-rotor-bearing model, which contains backlash, transmission error, eccentricity, gravity and input/output torque, is established, and the coupled lateral-torsional vibration characteristics are studied. Based on the equations of motion, the coupled spur gear-rotor-bearing system(SGRBS) is investigated using the Runge-Kutta numerical method, and the effects of rotational speed, error fluctuation and load fluctuation on the dynamic responses are explored. The results show that a diverse range of nonlinear dynamic characteristics such as periodic motion, quasi-periodic motion, chaotic behaviors and impacts exhibited in the system are strongly attributed to the interaction between internal and external excitations. Significantly, the changing rotational speed could effectively control the vibration of the system. Vibration level increases with the increasing error fluctuation. Whereas the load fluctuation has an influence on the nonlinear dynamic characteristics and the increasing excitation force amplitude makes the vibration amplitude increase, the chaotic motion may be restricted. The proposed model and numerical results can be used for diagnosis of faults and vibration control of practical SGRBS.     

含裂纹故障齿轮系统的非线性动力学研究

考虑时变啮合刚度、间隙非线性及传动误差的影响,针对试验齿轮箱中的单对齿轮传动建立齿轮副扭转振动的参数化动力学模型,对裂纹故障的非线性动力学机理进行研究。采用平均法分析齿轮裂纹模型的主共振及1/2亚谐共振的动力学响应;给出裂纹演化过程对齿轮系统啮合刚度及动力学行为的影响;通过幅频特性曲线、时域图、相轨迹图、Poincaré截面图及频谱图综合分析含有裂纹故障齿轮的振动特征;通过奇异性理论分析裂纹程度及传动误差所产生的内部激励与系统动力学分岔的关系,从而揭示了不同裂纹程度和传动误差所引起的不同分岔模式;最后通过试验提取含有裂纹故障齿轮的振动特征,试验结果验证了理论分析的结果,从而为齿轮系统裂纹故障的识别提供理论依据。     

基于接触有限元的齿轮-转子系统动态特性分析

考虑齿轮-转子系统各部件的弹性,基于接触有限元理论提出一种能够高保真模拟齿轮副连续啮合过程的动态特性分析方法。该方法利用实体有限元进行系统建模,可体现各部件的结构特征;基于接触有限元进行啮合过程仿真,可模拟系统的时变刚度、啮合冲击等真实激励进而得到全面准确的响应信息。以一直齿轮-转子系统为例进行啮合过程的数值仿真,利用中心差分法求得系统各动力学参量在时域上的响应,通过中心距偏差、动态传递误差、动态接触力等参数分析系统的弯曲振动、扭转振动、齿轮副的啮合特性及其耦合关系。研究结果表明：考虑各部件尤其是转子的弹性后,系统的非线性振动特性显著,齿轮副啮合存在明显的双边冲击及脱啮现象。     

Effects of a one-way clutch on the nonlinear dynamic behavior of spur gear pairs under periodic excitation

Nonlinear behavior analysis was used to verify whether a one-way clutch is effective for reducing the torsional vibration of a paired spur gear system under periodic excitation. The dynamic responses were studied over a wide frequency range by speed sweeping to check the nonlinear behavior using numerical integration. The gear system with a one-way clutch showed typical nonlinear behavior. The oscillating component of the dynamic transmission error was reduced over the entire frequency range compared to a system without a one-way clutch. The one-way clutch also eliminated unsteady continuous jump phenomena over multiple solution bands, and prevented double-side contact, even with very small backlash. Installing a one-way clutch on both sides of the gear system was more effective at mitigating the negative effects of external periodic excitation and various parameter changes than a conventional gear system without a one-way clutch.     

随机激励作用下的齿轮时变系统稳态响应研究

在外部随机激励作用下,对齿轮传动系统时变啮合刚度的稳态动力响应进行了研究,建立了包含外部随机激励力的周期时变啮合刚度的直齿轮副模型。为了计算齿轮系统的响应,采用了一种非常有效的方法,称为迭代谱方法。该方法主要应用在频域中的推导,并且可提供响应的显式功率谱密度,功率谱密度响应可表示为双谱的函数,即参数系统双时相脉冲响应的双线性傅里叶变换。     

关于计算机模拟齿轮噪声振动源的研讨

本文提出了一种计算方法,用以模拟作为齿轮噪声振动源一对渐开线圆柱直齿轮运动,即通过由静态传动误差间接处理内激励力,解出以传动误差为耦合变量的振动微分方程来得到动态传动误差;并建立了相应的具有频谱分析功能的数字模拟系统,试图为振动源机制的研究提供一个有力的工具。     

大兆瓦级风电齿轮箱耦合动态特性及结构噪声分析

风电齿轮箱是风电机组的重要组成部分,其动态性能的好坏直接影响整个机组的性能。建立了具有两级行星加一级平行轴齿轮传动的大兆瓦级风电齿轮箱齿轮-传动轴-轴承-箱体系统耦合非线性动力学有限元模型,采用Lanczos法对齿轮箱系统进行耦合模态分析。在综合考虑直斜齿轮时变啮合刚度、齿轮误差及齿轮啮合冲击等内部激励因素综合作用影响下,运用直接积分法对整个风电齿轮箱系统进行了动态响应求解,从而获得齿轮箱各点的振动位移、速度及加速度动态评价指标,并且对系统结构噪声进行了分析。研究结果可为大兆瓦级风电齿轮箱的动态性能优化提供参考。     

Dynamic behavior analysis of spur gears with constant & variable excitations considering sliding friction influence

A new analytical model of a spur gear system with sliding friction is presented. Unlike previous models, the excitation consists of two parts: the rotational driving speed of the pinion and the drag torque acting on the gear. The proposed model was validated with the finite element model. Using numerical method, the steady state resolutions was obtained to mainly demonstrate the nonlinear characteristics under both constant and variable excitations. The results obtained illustrate that sliding friction could introduce additional vibration. Moreover, the sliding friction even could decrease the dynamic transmission errors under proper operation condition. Further, the bifurcation diagram was plotted to show the influence of the rotational driving speed of the pinion on the dynamical characteristic of the gear system. Finally, the fluctuated excitation was used to exhibit their different effects on the gear system, which should form the basis of further analytical and experimental work in the gear dynamic area.     

Nonlinear dynamics of a spur gear pair with time-varying stiffness and backlash based on incremental harmonic balance method

In this paper the incremental harmonic balance method (IHBM) is extended to analyze the nonlinear dynamics of a spur gear pair and some new results are obtained. At first the dynamical model of a spur gear pair is established, where the backlash, time-varying stiffness and static transmission error are all included. Here the time-varying stiffness and static transmission error are represented by the multi-order harmonic series through Fourier expansion. Based on the IHBM, the general forms of the periodic solutions for this system are founded, which is useful to obtain the solutions with arbitrary precision. And the difference between the frequency-response to the multi-order and single-order harmonic is analyzed. Then the effects of the multi-order harmonic on the kinds of the periodic solutions are also investigated by IHBM, and the comparison with the numerical solutions shows the validity of the proposed method. At last the influence of the damping ratio and the excitation amplitude on frequency-response curves is researched, which presents some useful information to analyze and/or control the dynamics of gear system.