Looking for Leaks in all the Small Spaces

This article describes use of photoacoustics by automakers to track and tackle leakage problems. Photoacoustics uses momentary heat from a light source to excite acoustic waves. Laser Imaging Systems of Punta Gorda, FL, developed the idea of photoacoustic leak detection. Dowling worked with Ford in developing leak localization as part of a team that was put together by the National Center for Manufacturing Sciences. Once a leak is sensed, a technique originally developed for a US Navy underwater acoustics program deploys to pinpoint its place. Vertical location is known already. Vacuum Instrument and Laser Imaging Systems are building the alpha prototype now.

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Estimating the Effective Depth of Laser Imaging Systems in Various Ocean Environments.

10.21236/ada310173 ◽

1996 ◽

Author(s):

Jerry L. Gorline

Keyword(s):

Imaging Systems ◽

Laser Imaging ◽

Effective Depth

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New Leak Location Approaches for Gas Pipelines Using Acoustic Waves

Volume 3: Operations, Monitoring, and Maintenance; Materials and Joining ◽

10.1115/ipc2018-78327 ◽

2018 ◽

Author(s):

Cuiwei Liu ◽

Yuxing Li ◽

Qihui Hu ◽

Wuchang Wang ◽

Yazhen Wang ◽

...

Keyword(s):

Natural Gas ◽

Acoustic Waves ◽

Economic Loss ◽

Transportation Systems ◽

Gas Pipelines ◽

Natural Gas Pipelines ◽

New Methods ◽

Leak Location ◽

Localization Errors ◽

Leak Localization

Natural gas is a vital energy carrier which can serve as an energy source, which is extremely vulnerable to leakages from pipeline transportation systems. The required ignition energy is low. Although the safety of natural gas pipelines has been improved, the average economic loss of natural gas accidents, including leaks, is large. To solve these problems, an acoustic leak localization system is designed and researched for gas pipelines using experiments with methods proposed according to different application situations. The traditional method with two sensors installed at both ends can be improved by a newly proposed combined signal-processing method, which is applied for the case that it is necessary to calculate the time differences with data synchronicity. When the time differences cannot be calculated accurately, a new method based on the amplitude attenuation model is proposed. Using these methods, the system can be applied to most situations. Next, an experimental facility at the laboratory scale is established, and experiments are carried out. Finally, the methods are verified and applied for leak localization. The results show that this research can provide a foundation for the proposed methods. The maximum experimental leak localization errors for the methods are −0.592%, and −7.62%. It is concluded that the system with the new methods can be applied to protect and monitor natural gas pipelines.

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Performance Enhancement of Gain-Modulated 3D Imaging System by Multi-Pulse Accumulation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.475-476.259 ◽

2013 ◽

Vol 475-476 ◽

pp. 259-262

Author(s):

Fei Wang

Keyword(s):

3D Imaging ◽

Performance Enhancement ◽

Imaging System ◽

Imaging Systems ◽

Laser Imaging ◽

Range Error ◽

Accumulation Method ◽

Accuracy Performance

Range accuracy is one of the key parameters for 3D laser imaging systems. A gain-modulated 3D imaging system employing multi-pulse accumulation method is proposed to improve the range accuracy performance. Experiments results show that the range error decreases exponentially with the number of accumulated laser echoes.

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