Chapter 37
A Method of Vacuum Leak Detecting
Based on Acoustic Emission
Characteristics Analysis
Qi Lei, Sun Lichen, Liu Gaotong, Rui Xiaobo, Liu Tao, and Wang Lina
Abstract In the view of space science and technology is developing, the number
of spacecraft in orbit is increasing. Space environment including vacuum, vibration,
alternating temperature, micro-meteorites and space debris threatens the structure
safety of spacecraft. Once a leak in the spacecraft structure occurs, the pressure of the
capsule will drop, which will have a significant impact on the safety of the astronauts.
When a leak occurs, the acoustic signal is generated and a method for vacuum leak
detection can be used based on characteristics analysis. In this paper, the vacuum leak
detection principle is described, and tested by the proposed experimental platform.
By characteristic analysis, the signals generated by three different leak holes of 1.0,
1.5 and 2.0 mm are collected and compared with the background acoustic signal
by the pump without leakage. The Experiment data show that the signal frequency
of the pump running is below 20 kHz. The leak signal is above 20 kHz, which is
obviously distinguished from the background noise. When the diameter of the leak
hole increases, the energy of leak signal becomes larger, but the high frequency
component in the signal decreases. The characteristics analysis of leak acoustic
emission signal in this paper is meaningful to the leak detection of spacecraft.
37.1 Introduction
With the increase of human space activities, more and more space debris are left in
earth orbit. Once space debris collides with spacecraft, the spacecraft cabin damage
and gas leak prone to occur. Therefore, it is very important to detect the leak of spacecraft in orbit. Leak location and leak rate assessment are two major tasks of leak detection. The gas leak of spacecraft cabin is from atmosphere to vacuum. The pressure
difference is small and the acoustic signal generated by the leak is extremely weak
mixed with the background noise of pump running, which increases the difficulty of
acoustic leak detecting. After 2000, NASA, ESA and other institutions have studied
a series of on-orbit leak detection methods [1, 2], including optical method, acoustic
Q. Lei (B) · S. Lichen · L. Gaotong · R. Xiaobo · L. Tao · W. Lina
Institute of Spacecraft Environment Engineering, Beijing, China
e-mail: qilei511@126.com
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
G. Shen et al. (eds.), Advances in Acoustic Emission Technology, Springer Proceedings
in Physics 259, https://doi.org/10.1007/978-981-15-9837-1_37
419
A Method of Vacuum Leak Detecting
Based on Acoustic Emission
Characteristics Analysis
Qi Lei, Sun Lichen, Liu Gaotong, Rui Xiaobo, Liu Tao, and Wang Lina
Abstract In the view of space science and technology is developing, the number
of spacecraft in orbit is increasing. Space environment including vacuum, vibration,
alternating temperature, micro-meteorites and space debris threatens the structure
safety of spacecraft. Once a leak in the spacecraft structure occurs, the pressure of the
capsule will drop, which will have a significant impact on the safety of the astronauts.
When a leak occurs, the acoustic signal is generated and a method for vacuum leak
detection can be used based on characteristics analysis. In this paper, the vacuum leak
detection principle is described, and tested by the proposed experimental platform.
By characteristic analysis, the signals generated by three different leak holes of 1.0,
1.5 and 2.0 mm are collected and compared with the background acoustic signal
by the pump without leakage. The Experiment data show that the signal frequency
of the pump running is below 20 kHz. The leak signal is above 20 kHz, which is
obviously distinguished from the background noise. When the diameter of the leak
hole increases, the energy of leak signal becomes larger, but the high frequency
component in the signal decreases. The characteristics analysis of leak acoustic
emission signal in this paper is meaningful to the leak detection of spacecraft.
37.1 Introduction
With the increase of human space activities, more and more space debris are left in
earth orbit. Once space debris collides with spacecraft, the spacecraft cabin damage
and gas leak prone to occur. Therefore, it is very important to detect the leak of spacecraft in orbit. Leak location and leak rate assessment are two major tasks of leak detection. The gas leak of spacecraft cabin is from atmosphere to vacuum. The pressure
difference is small and the acoustic signal generated by the leak is extremely weak
mixed with the background noise of pump running, which increases the difficulty of
acoustic leak detecting. After 2000, NASA, ESA and other institutions have studied
a series of on-orbit leak detection methods [1, 2], including optical method, acoustic
Q. Lei (B) · S. Lichen · L. Gaotong · R. Xiaobo · L. Tao · W. Lina
Institute of Spacecraft Environment Engineering, Beijing, China
e-mail: qilei511@126.com
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
G. Shen et al. (eds.), Advances in Acoustic Emission Technology, Springer Proceedings
in Physics 259, https://doi.org/10.1007/978-981-15-9837-1_37
419