426
Q. Lei et al.
(a) Amplitude
(b) ASL
(c) Emergy
(d) RMS
Fig. 37.7 Characteristic parameters of leak acoustic emission signals
37.5 Conclusion
The leak problem in spacecraft in-orbit is very serious, which threatens the spacecraft
in-orbit operation and the life safety of astronauts. It is very important to judge the
leak accurately and in time, determine the leak location and evaluate the leak rate
for the disposal of leak accidents. In this paper, the acoustic emission signals of
three typical kinds of leak are analyzed through spectrum analysis and characteristic
parameter analysis. The following conclusions are drawn:
1. The leak acoustic emission signal is a broadband signal whose energy is mainly
concentrated below 400 kHz. The larger the leak hole is, the larger the amplitude
is, but the frequency band of leak signal with small leak hole is wider than that
with a large leak hole.