高超声速飞行器模型振动及传力特性研究
Vibration and Load Transmission Characteristics of Hypersonic Vehicle Model

提出了一种应用加速度信号研究飞行器试验模型传力特性的方法，采集飞行器试验模型不同位置的振动加速度信号，应用小波包分解方法对采集到的加速度信号进行预处理。对滤波后的信号采用经验模态分解（empirical mode decomposition, 简称EMD）方法进行处理，得到信号的本征模态函数(intrinsic mode functions，简称IMFs)，并通过相关系数判别并剔除伪分量。对剩余IMF分量进行希尔伯特（Hilbert）变换，得到信号的希尔伯特谱，并计算不同方向上飞行器试验模型壳体与内部结构加速度信号的能量分布差异，判断各方向上飞行器试验模型传力特性的优劣。结果表明：该方法能够用于飞行器模型的传力特性研究，且飞行器模型各向传力误差分别为0.189 1,0.098 1,0.0377，大部分气动载荷能够有效地从飞行器壳体传递到其内部结构，垂直方向上的力学传递性能最佳。
In this paper, the load transmission characteristics of a hypersonic vehicle model are analyzed by vibration. First, the vibrating acceleration signals are collected at different positions, preprocessed using wavelet package decomposition, then decomposed into a series of intrinsic mode functions (IMFs) using empirical mode decomposition (EMD).The untrue IMFs are removed using the correlation coefficient method, and the Hilbert spectrum of the remaining IMFs is obtained after the Hilbert transform. Finally, the energy distribution differences among different positions in each direction are computed in order to estimate the load transmission characteristics of the hypersonic vehicle model. The results show that most of the air dynamic force can be successfully transmitted inside with low transmission error, and that it performs best vertically.