不确定性转子系统的随机有限元建模及响应分析

随机特性和随机载荷会引起转子系统动力响应的不确定性,是转子动力学分析中的重要影响因素.本文基于Timosheke梁理论,把转轴的材料和几何随机特性表示为一维随机场函数,推导出随机转轴有限元列式,建立转子系统随机动力学模型,并给出随机载荷作用下随机转子系统动力响应统计量的分析方法.分别对线性和非线性涡轮泵转子系统进行了随机动力响应分析,并同Monte Carlo仿真结果进行对比,结果表明所建立的随机有限元动力学模型和给出的随机响应分析方法是合理可行的,可以有效应用于实际转子系统随机动力学分析和设计中.

Stochastic finite element modeling and response analysis of uncertain rotor systems

Based on the Timosheko beam theory, the stochastic finite element of a rotating shaft was proposed for the rotor system modelling in which material and geometric random properties were described as one dimensional stochastic field functions. The random response analysis method was developed in order to determine the statistics of dynamic responses of stochastic rotor systems under random loads. A linear and a nonlinear turbopump rotor systems were employed to compare the results obtained by the proposed mode, method and Monte Carlo simulation. And the numerical results, which coincide well with Monte Carlo simulation data, demonstrate that the proposed stochastic model and method are feasible and efficient in actual rotor system analysis and design.