考虑模型形式误差的转子动力学修正及确认

Model Updating and Validation for Bearing-Rotor System at Working Speed Considering Model-Form Error

研究考虑模型形式误差的轴承-转子系统工作转速下的动力学模型修正和确认方法。首先,介绍了模型形式误差以及基于复模态特征值灵敏度的模型修正理论;然后,在此基础上以轴承-柔性转子系统为仿真算例,考虑模型形式误差,使用系统在恒定工作转速下的涡动频率和阻尼参数,同时对轴承的支承刚度、支承阻尼和转盘的直径转动惯量参数进行修正;最后,通过不平衡响应结果对修正模型进行了确认。仿真结果显示,考虑模型形式误差时的修正参数最大误差仍有-10.1%,而修正后特征值实部最大误差为0.95%,特征值虚部最大误差为-1.15%,修正后不平衡响应与目标模型基本重合。研究表明,考虑模型形式误差时轴承-转子系统的修正方法是稳健的,也是有效可行的。

Structure dynamical model updating and validation for bearing-rotor system at working speed considering model-form error is presented. The theory of model-form error, model updating based on complex eigenvalue sensitivity analysis is successfully accomplished in this piece of work. The updating for simulation example about flexible rotor-bearing system at working speed, considering model-form error, is performed to bearing stiffness, bearing damping and diameter moment of inertia parameters using wheel frequency and damping as objective residues. The updated model is validated through unbalance response prediction. The simulation results show that the maximum residual errors of updated parameter is still -10.1%, but the maximum residual errors for the real part of updated eigenvalue is 0.95% and for the imaginary part is -1.15% even taking into 2% model-form error account in model updating. The unbalance response prediction of the updated model matches the target model unbalance response quite well. The results, in no doubt, proved the effectiveness and robustness of the model updating method considering model-form error using wheel frequency and damping for bearing-rotor system at working speed. © 2017, Editorial Department of JVMD. All right reserved.