为准确揭示叶片阻尼系统的动力学特征,首次引入融合时域法(描述非线性力的准确性)和频域法(求解线性系统的高效性)为一体的时频域交互法,对基于微滑移摩擦模型的凸肩阻尼结构叶片系统进行了动力响应分析,并与时域法、频域法的计算结果做了比较.计算结果显示:在一定的参数条件下,时频域交互法的计算时间与一阶谐波平衡法相近,仅相当于四阶Runge-kutta法的1/10,相对误差值却不到一阶谐波平衡法的1/2,且保持稳定.研究表明:时频域交互法对于计算微滑移干摩擦阻尼叶片振动响应具有可用性,该方法克服了一阶谐波平衡法无法将微滑移模型的准确性体现在动力学分析中的不足,而且计算效率高.
An alternating frequency/time domain method (AFT) is presented to calculate the dynamic characteristics of damping blade systems accurately. The dynamic response of damping blade systems is predicted based on the microslip dry friction model, and the computational accuracy and efficiency are compared with those by the time domain method and the frequency domain method. The results indicate of that under certain parameter conditions, the calculation time of AFT method is similar to that of the one-term harmonic balance method (HBM) and is just ten percent of that of the fourth-order Runge-Kutta method, and the relative error of the result with the AFT method is less than half that with HBM. These findings confirm the practicability of the AFT method in computing dynamic response of damping blade systems based on the microslip dry friction model. Unlike HBM, the AFT method can achieve the accuracy of microslip dry friction model in dynamics analysis and has high computational efficiency.