超高速撞击声发射信号在载人航天器加筋结构的传播特性实验研究

为研究超高速撞击声发射信号经过载人航天器加筋结构后的传播规律,分别在平板结构和加筋结构上模拟高速撞击实验,利用传感器阵列采集高速撞击产生的声发射信号。结合小波和傅里叶分析方法从板波模态、频域以及时域三方面分析加筋结构对声发射信号传播特性的影响,并研究成坑和穿孔损伤模式下声发射信号的传播规律。结果表明:加筋板中的信号高频部分比平板中高频部分能量少,筋体对信号高频部分有滤波效果。加筋结构受高速撞击产生穿孔损伤时,S0模态声波的能量增多。研究成果可为载人航天器结构的高速撞击感知与定位技术提供有利参考。 

Experimental study on transmission characteristics of acoustic emission signal caused by hypervelocity impact on manned spacecraft with stiffened panel

In order to study the transmission characteristics of acoustic emission signal caused by hypervelocity impact on manned spacecraft with stiffened panel, the hypervelocity impact is simulated on both flat panels and stiffened panels, and the acoustic emission signals are collected by sensor array. The effects of the strengthening ribs of the panel on the AE signals are analyzed in the aspects of wave mode, frequency domain and time domain by methods of wavelet and Fourier transform. The transmission characteristics of acoustic emission signals corresponding to distinct damage patterns of pits and perforations are studied. The results illustrate that the high frequency components of AE signal in stiffened panel have less energy than that in flat panel, which implies that stiffened panel has filtering effect on high frequency components of the emission signal. The energy of SO mode will increase when the damage patterns are perforations which resulted from hypervelocity impact. The research findings provide a favorable reference to the detection and localization technique for hypervelocity impact on manned spacecraft with stiffened panel.