航天器舱壁加筋结构中泄漏声波传播特性与泄漏定位影响研究

Research on Propagation Characteristic of Leakage Acoustic Emission Signal in Spacecraft Stiffened Plate and Its Effect on Leakage Location Method

为解决泄漏定位方法受航天器加筋结构影响而出现较大定位误差的问题,提出一种过筋系数的计算方法,根据过筋系数分析加强筋对不同频率信号的影响以选择合适的滤波频率,提高泄漏定位算法的准确性。通过实验对加强筋前后泄漏声波的时域及频域特征进行比较,得到加强筋对不同频率声波滤波特性曲线,并选择合适的声波频带进行泄漏定位。实验结果表明:泄漏声波通过加强筋后,信号幅值明显衰减,加强筋对泄漏信号有梳齿状滤波作用,在100〜400 kHz频率范围内的低频成分衰减更显著,通过选择合适的泄漏声波频率,可以明显提高泄漏定位精度。

The leakage location method will have a larger error when affected by the stiffener structure of the spacecraft.To solve this problem,a method of calculating the stiffener passing coefficient was proposed.According to the stiffener passing coefficient,the influence of stiffeners on different frequency signals was analyzed to select the appropriate filtering frequency and thus to improve the accuracy of leakage location algorithm.The differences of the signals before and after passing the stiffeners in both time domain and frequency domain were compared,and a filtering characteristic curve of different frequency bands which could guide the frequency selection for leakage location methods was obtained.A leakage location experiment was conducted and the results showed that the amplitude of the leakage signal attenuated significantly after passing the stiffeners,and the stiffeners had a comb-shape filtering effect on the leakage signals.The attenuation was relatively larger in the lower frequency band of 100〜400 kHz.By selecting the proper frequency,the accuracy of the leakage location method could be improved.