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提出了一种高效的颤振预测分析方法,将之应用于跨声速颤振边界分析及结构参数影响研究中。本方法基于频域颤振分析V-g方法,为气弹系统提供一定的人工阻尼使之保持简谐运动状态,从而将结构动力学方程转换到频域内。然后通过高效的谐波平衡法得到一系列简谐运动频率下的气动力描述函数矩阵,结合频域结构方程,将气弹系统的稳定性问题转化为广义特征值求解。结果表明:本方法计算得到的颤振边界与高精度的时间推进方法非常吻合,分析效率有了明显的提升,而且当结构参数发生变化后,只需进行若干次广义特征值求解即可得到新的颤振边界,无需像时间推进方法一样开展大量的气动/结构耦合数值模拟。
An efficient flutter prediction analysis method is proposed, which is applied to the analysis of transonic flutter boundary and the influence of structure parameters. The method is based on the V-g method of frequency-domain flutter analysis, which provides certain artificial damping for the gas-spring system to keep it in a state of simple harmonic motion so as to transform the structural dynamic equation into the frequency domain. Then, a series of aerodynamic description function matrices with simple harmonic motion frequencies are obtained through the efficient harmonic balance method, and the stability of the gas-air-missile system is transformed into the generalized eigenvalue solution by combining with the structural equation of frequency domain. The results show that the flutter boundary calculated by this method is in good agreement with the time-propulsion method with high accuracy, and the analysis efficiency is obviously improved. Moreover, when the structural parameters change, only a few generalized eigenvalues can be obtained to solve the problem. Of the flutter boundary, there is no need to carry out a large number of aerodynamic / structural coupling numerical simulations as the time advance method.