具有不同辐板布置斜齿轮传动系统的动态特性研究

研究了齿轮结构参数齿轮传动系统动态特性的影响。用三维有限元计算了航空齿轮常用的三种辐板支承形式和不同轮缘与轮幅尺寸下齿轮副的刚度波动，用Ｆｏｕｒｉｅｒ级数法讲义了齿轮结构参数对其传动系统固有频率及动载荷的影响，以及附加阻尼的作用。     

齿轮装置传动系统动态特性分析

齿轮传动装置在工作过程中，由于受内部动载荷和外部动载荷的作用，将产生扭转振动。其振动的强弱不仅取决于单对齿轮，而且与整个传动系统中各环节的能量分布是否均匀有关。本文以SY131汽车变速器为例对齿轮传动装置动态性能进行了分析及计算。     

刚柔耦合机械系统动力学仿真

有限元技术和虚拟样机技术相结合，实现了对高速机械系统刚柔耦合的动力学仿真，并以一个算例说明了该方法的可行性。     

行星齿轮传动系统动力学研究进展

详细评述了国内外学者对行星齿轮传动系统在动力学模型、动态响应、动载荷和均载、固有特性等方面的研究状况,介绍了2种集中参数模型用不同方法求解系统动态响应的结果,动载荷和均载的理论与试验研究,固有特性的规律及系统参数对固有特性等方面的研究成果.最后,根据行星齿轮传动系统研究的发展趋势,提出了需要进一步研究的几个问题:含摩擦力的行星齿轮动力学特性研究,复合行星齿轮动力学特性研究和齿轮系统的振动控制研究.     

大型挠性航天器刚柔耦合动特性分析

为研究装载周边桁架式可展开天线的航天器在进行姿态调整时的动态响应特性,建立了航天器动力学模型,并对姿态调整过程的动态响应进行数值求解.首先建立由可展开天线、太阳帆板和中心平台组成的整星有限元模型并求出无约束边界条件下的固有频率和振型.通过有限元模型和Adams联合仿真建立航天器零次刚柔耦合动力学模型并求得姿态调整过程整星的位移和转角以及太阳帆板和可展开天线的动态响应.结果表明:整星的低阶模态特性主要体现在太阳帆板和天线连接杆的变形上,而天线结构无变形;航天器在进行姿态调整时,挠性部件在做大范围整体运动的同时发生显著的结构振动;航天器完成姿态调整后天线几何中心点在平衡位置附近继续振荡.     

基于浮动坐标法的刚柔耦合定位平台力学模型

精密定位平台由于机械摩擦造成精度受限,难以满足大行程、高精度定位的运动要求。本文结合宏微复合结构,提出了一种单驱动刚柔耦合定位平台。相对于现有的宏微复合平台,大幅简化了机械结构和运动控制系统的设计。基于浮动坐标法和有限元法建立了单驱动刚柔耦合定位平台的静力学和动力学模型,并与商业软件ABAQUS及简化解析模型的分析结果进行对比,最大相对误差分别为1.6%和3.72%,证明了该理论模型具有较高的预测精度,可为刚柔耦合平台的优化设计及精密运动控制提供参考。     

椭圆齿轮传动系统非线性动态特性分析

为获得椭圆齿轮副工作时的振动规律,以实现其稳定、高效传动,在分析椭圆齿轮固有特性的基础上对椭圆齿轮非线性动力学特性进行了研究。以齿轮动力学理论为基础,建立考虑时变啮合刚度、齿侧间隙、静态传递误差、粘弹性阻尼的椭圆齿轮非线性动力学模型,利用四阶变步长Runge-Kutta数值方法对椭圆齿轮传动系统非线性动力学方程进行求解,绘制了系统的位移响应,相轨迹以及Poincaré映射,得到激励频率、阻尼比、时变啮合刚度、以及内部激励4个控制参数对传动系统动态响应的影响。椭圆齿轮副动力学模型的建立、求解和参数影响分析可以为后续的动态设计、不同参数下的振动响应趋势预测以及降噪提供一定的理论依据。     

弯扭耦合齿轮传动系统固有频率与振型计算的传递矩阵法

对齿轮传动系统弯曲和扭转两种振动形式进行了综合分析,导出了计算系统耦合情况下的固有频率与振型的传递矩阵公式。计算结果表明,考虑弯曲振动和扭转振动耦合情况的齿轮系统的固有频率与不考虑耦合情况的计算结果相差很大,因而对齿轮系统的设计具有重要意义.     

柔性销轴式人字齿星型轮系均载特性

为研究人字齿星型轮系各路功率分流载荷分配机理,提高齿轮箱承载能力,采用节点有限元法建立柔性销轴式齿轮涡扇发动机人字齿星型轮系动力学模型.研究当量啮合误差下星型轮系动态均载性能,分析误差激励、销轴结构、工况参数对系统均载特性的影响.结果表明:齿轮偏心误差使中心齿轮振动轨迹偏离原点,是造成不均载的主要原因;系统均载系数随误差增加呈线性增加,且制造误差的影响大于安装误差;柔性销可以明显改善系统均载性能,在4种星轮柔性销轴中Montestruc改进的柔性销均载性能最佳;系统的均载系数随输入转速增加呈增大趋势,共振会导致系统的均载性能急剧下降;均载性能随系统承载功率增大而变好,且功率变小,柔性销对系统的均载性能改善的优势更加明显.     

风电齿轮箱齿轮传动系统非线性因素影响分析

针对风力发电机齿轮箱在实际风场中工况复杂的问题,采用集中质量参数法建立了风电齿轮箱传动系统高速级齿轮滚动轴承耦合动力学模型,考虑了传动系统的综合啮合刚度、误差激励、齿面侧隙和轴承径向刚度等非线性影响因素,对1.5 MW风力机齿轮箱传动系统的非线性动力学模型进行了仿真计算分析.采用Runge-Kutta法对模型进行求解得到传动系统的时域波形和幅频响应.结果表明:较小齿面侧隙会使系统出现较大振动响应,随着齿面侧隙增大,系统振动位移减小,会导致系统从周期走向混沌响应;轴承游隙的存在使系统产生混沌响应,呈现出非周期的特征.     

Effect analysis of friction and damping on anti-backlash gear based on dynamics model with time-varying mesh stiffness

A nonlinear model of anti-backlash gear with time-varying friction and mesh stiffness was proposed for the further study on dynamic characteristics of anti-backlash gear. In order to improve the model precision, applied force analysis was completed in detail, and single or double tooth meshing states of two gear pairs at any timing were determined according to the meshing characteristic of anti-backlash gear. The influences of friction and variations of damping ratio on dynamic transmission error were analyzed finally by numerical calculation and the results show that anti-backlash gear can increase the composite mesh stiffness comparing with the mesh stiffness of the normal gear pair. At the pitch points where the frictions change their signs, additional impulsive effects are observed. The width of impulsive in the same value of center frequency is wider than that without friction, and the amplitude is lower. When gear pairs mesh in and out, damping can reduce the vibration and impact.     

Dynamic modeling and simulation for the rigid flexible coupling system with a non-tip mass

The rigid flexible coupling system with a mass at non-tip position of the flexible beam is studied in this paper. Using the theory about mechanics problems in a non-inertial coordinate system, the dynamic equations of the rigid flexible coupling system with dynamic stiffening are established. It is clearly elucidated for the first time that, dynamic stiffening is produced by the coupling effect of the centrifugal inertial load distributed on the beam and the transverse vibration deformation of the beam. The modeling approach in this paper successfully solves problems of popular modeling methods nowadays: the derivation process is too complex by using only one dynamic principle; a clearly theoretical mechanism for dynamic stiffening can't be offered. First, the mass at non-tip position is incorporated into the continuous dynamic equations of the system by use of the Dirac function and the Heaviside function. Then, based on the conclusions of orthogonalization about the normal constrained modes, the finite dimensional state space equations suitable for controller design are obtained. The numerical simulation results show that: dynamic stiffening is included in the first-order model established in this paper, which indicates the dynamic responses of the rigid flexible coupling system with large overall motion accurately. The results also show that the mass has a softening effect on the dynamic behavior of the flexible beam, and the effect would be more obvious when the mass has a larger mass, or lies closer to the tip of the beam.     

输电塔塔-线体系动力特性

为更清楚地掌握输电塔塔-线体系动力特性,基于ANSYS软件建立输电塔塔-线体系有限元分析模型,并以典型设计500kV输电线路5A-ZM2型塔为例,对单塔双线模型和三塔四线模型的振动频率进行了比较.数值分析结果表明:单塔双线模型满足精度要求且简便易行,可用于实际工程的有限元建模.此外,对单塔双线模型进行模态分析,获得了塔-线体系的频率范围,结果表明:输电塔塔-线体系频率比较密集,前159阶振型均反映为绝缘子和输电线的振动,160阶振型以后才反映输电塔振动的频率.     

Dynamics of vehicle-pavement coupled system based on a revised flexible roller contact tire model

A revised flexible roller contact tire model (RFRC tire model) is proposed, which considers not only the geometric and flexible filtering effect, but also tire damping and pavement displacement. A vehi-cle-pavement coupled system is modeled as a two DOF oscillator moving along a simply supported beam on a linear viscoelastic foundation. By using the Galerkin’s and Direct Integral method, dynamical responses of the vehicle-pavement coupled system are obtained based on the RFRC tire model and the traditional ...     

Theoretical and experimental study on non-linear vibration characteristic of gear transmission system

In order to investigate the vibration of gear transmission system with clearance, a vibratory test-bed of the gear transmission system was designed. The non-linear dynamic model of the system was presented, with consideration of the effects of nonlinear dynamic gear mesh excitation, flexible rotors and bearings. Integration method was used to investigate the non-linear dynamic response of the system. The results imply that when the mesh frequency is near the natural frequency of gear pair, it is the first primary resonance, the bifurcation appears, and the vibration becomes to be chaotic motion rapidly. When the speed is close to the natural frequency of the first-order bending vibration, it is the second primary resonance, the periodic motion changes to chaos by period doubling bifurcation. The vibratory measurement of test-bed of the gear transmission system was performed. Accelerometers were employed to measure the high frequency vibration. Experimental results show that the vibration acceleration of the gear transmission system includes mesh frequency and sideband. The numerical calculation results of low speed can be validated by experimental results basically. It means that the presented non-linear dynamic model of the gear transmission system is right.     

通廊耦连结构动力性能分析

讨论了由通廊连在一起的厂房或构筑物结构体系的动力计算方法，并通过对一实际结构振动特性的分析，探讨了这种结构体系的动力反应特征。     

基于多体系统动力学的悬架虚拟样机库

从悬架的运动学和柔顺性(K&C)关系入手,以多体系统动力学为理论依据,建立了包含多种悬架的虚拟样机库。该虚拟样机库具有:①开放性。通过修改参数可以方便地构建用户自己的悬架虚拟样机;②实用性。虚拟样机库中的悬架都是企业实车悬架,对其仿真得出的悬架K&C特性具有重要的工程参考价值;③基础性。可快速构建多种前后悬架布置形式的整车虚拟样机。该虚拟样机为悬架产品乃至底盘产品的综合化、集成化、并行化设计打下了基础。     

基于ANSYS的变速器齿轮有限元静力学分析

用有限元分析方法对变速器齿轮的静力学特性进行理论计算和研究。建立各齿轮的有限元模型,应用有限元分析软件ANSYS对模型进行分析计算,得出各齿轮的应力和应变,并对计算结果进行静态分析。