【作者】 宣海军；

【导师】 童水光； 吴荣仁；

【作者基本信息】 浙江大学 ， 化工过程机械， 2004， 博士

【摘要】 粘弹性橡胶阻尼器(Viscoelasic Elastomer Damper，VED)自20世纪中期以来就被应用于旋转机械，它通过耗散能量来抑制转子系统的振动。VED具有结构紧凑、使用方便、减振效果好、成本低等优点，而在高速旋转机械中有较为广泛的应用。本文结合理论和试验研究橡胶O型圈阻尼器(Elastomer O-Rings Damper,EORD)支承转子系统的动力学特性，并将EORD作为高速柔性悬臂轴的减振支承应用在100000r／min超高速旋转试验台中。 论文的第一部分，将Timoshenko连续梁轴模型应用于柔性轴，轮盘是刚性和非对称的集总单元，推导出适合于分析复杂转子系统动力学特性的有限单元运动方程，运动方程中同时考虑了不平衡质量和偏斜轮盘的激励作用。理论研究两端EORD支承轴向非对称安置单盘转子系统的动力学特性。采用Kelvin-Voigt线性粘弹性模型表示EORD的动态特性。研究EORD支承刚度、损耗因子和质量参数对转子系统模态频率和稳定性的影响。计算结果表明，可通过优化选取EORD的特征参数来提高特定转子系统的稳定性。通过数值仿真和实验研究远轴端EORD支承的单盘柔性转子系统的不平衡响应。理论分析表明，采用损耗因子在0.1至0.4之间的常用的橡胶O型圈，即可极大地降低一阶临界振动响应。不同不平衡条件下的动力学响应的试验和理论结果很接近。 论文的第二部分，将EORD应用于支承超速旋转试验台的高速柔性悬臂转子。在高速轴端安装模拟轮盘的试验，用于检验EORD，高速转子系统的不平衡响应和稳定性。成功完成试验转速要求为93500 r／min的透平膨胀机叶轮的超速试验。高阶临界转速的有限元分析结果与试验结果非常接近。 论文最后，从工程应用的角度提出EORD的设计建议，对本文的研究工作做简单的小结，提出进一步研究的建议。更多还原

【Abstract】 Viscoelastic elastomer damper (VED) have been applied in rotating machinery since the middle twentieth century. VED are implemented to suppress the rotor system’s vibration by dissipate dynamic energy. VED are used some abroad in high-speed rotating machinery for its simple, convenience, good vibration suppress, low costs. This thesis investigates the dynamic problem of rotor systems with Elastomer O-Rings Damper(EORD) supports and apply EORD in an ultra-speed spin tester for vibration decrement of the high-speed flexible overhung rotor.In the first part of this study, finite element motion equations are established to analysis dynamics of complex rotor system. Timoshenko beam shaft model is utilized to incorporate the flexibility of the shaft The disk is considered to be rigid and asymmetry. Unbalance and disk skew are considered in motion equation.The simulation investigations were conducted on a z-direction asymmetrically placed single-disk rotor system with two shaft ends supported in elastomer O-ring dampers. The dynamic characteristics of EORD are modeled using Kelvin-Voigt viscoelastic linear model. The effects of EORD stiffness and loss-factor and damper mass parameters on the modal frequency and stability are investigated. The results show that optimum values of the damper characteristic parameters can be achieved for a specific rotor system to improve the stability.Numerical simulations and experimental investigates were carried out for unbalance response of a single disk flexible rotor system with far shaft end mounted on EORD. Theoretical results showed that EORD, using general elastomer O-rings with loss-factor between 0.1 and 0.4, was enough to reduce first critical response vibrations of the experimental rotor system. Dynamic responses under different unbalance conditions showed excellent qualitative agreement between experimental and theoretical results.In the second part of this study, EORD is applied to an ultra-speed spin tester to support a flexible overhung rotor. The experiments with a simulated disk on the high speed shaft end was undertaken to test the EORD for the unbalance response and stability of the high-speed rotor system. The tests confirm the vibration decrement validity and linear dynamic characteristics of EORD. The spin testing of a turbine impeller with maximum spin speed 93 500 rpm was successfully finished. The finite element predictions of high critical speeds are shown to be close to the experimental results.Finally, the design guideline of EORD and the research conclusions and recommends are presented.更多还原