Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

CWT-Based Method for Identifying the Location of the Impact Source in Buried Pipes

연속웨이브렛 변환을 이용한 충격음 위치 규명

  • Kim, Eui-Youl (Dept. of Mechanical Engineering, Inha Univ.) ;
  • Kim, Min-Su (Dept. of Mechanical Engineering, Inha Univ.) ;
  • Lee, Sang-Kwon (Dept. of Mechanical Engineering, Inha Univ.) ;
  • Koh, Jae-Pil (School of Mechanical and Aerospace Engineering, Seoul Nat‘l Univ.)
  • 김의열 (인하대학교 기계공학과) ;
  • 김민수 (인하대학교 기계공학과) ;
  • 이상권 (인하대학교 기계공학과) ;
  • 고재필 (한국가스공사 연구개발원)
  • Received : 2009.08.17
  • Accepted : 2010.08.19
  • Published : 2010.11.01
Download PDF
⟨ Previous Next ⟩

Abstract

This paper presents a new method for indentifying the location of impact source in a buried duct. In a gas pipeline, the problem of leakage occurs due to the mechanical load exerted by construction equipment. Such leakage can cause catastrophic disasters in gas supply industries. Generally, the cross-correlation method has been used for indentifying the location of impact source in a pipeline. Since this method involves the use of the dispersive acoustic wave, it derives an amount of error in process of estimating the time delay between acoustic sensors. The object of this paper is to estimate the time delay in the arrival of the direct wave by using the wavelet transform instead of the dispersive wave. The wavelet transform based method gives more accurate estimates of the impact location than the cross-correlation method does. This method is successfully used to identify the location of impact force in an actual buried gas duct.

본 연구에서는 지하에 매설된 가스 파이프에 가해진 충격의 위치를 탐지하기 위한 개선된 방법을 제시하고 있다. 가스 파이프에서 가스 누출은 건설 기계 장비에 의한 기계적 충격에 의해 발생하며, 가스 이송산업계에 치명적인 재해을 발생시킬 수 있다. 이와 같은 문제를 초기에 발견하고 조치를 취하기 위해 기존에는 충격 위치 탐지를 위해 상관 관계 기법이 사용되어 왔다. 하지만, 외부 충격에 의해 파이프 따라 전파되는 음향파의 분산 특성은 양쪽 센서에 측정되는 도착 시간을 사용하여 센서 사이에 도착 시간 지연을 예측하는데 상당한 에러를 발생 시킬 수 있다. 그래서 이 논문에서는 분산파 대신 직접파의 도착 시간 지연을 측정하기 위해 웨이블렛 기법을 사용하였다. 제안된 방법은 지하에 매설된 실제 가스 파이프에서 측정된 음향 신호에 적용하여 기존의 상관 관계 기법에 비해 외부 충격 위치를 추정하는데 보다 효과적임을 확인하였다.

Keywords

References

  1. Farahnak, S. D., et al, 2000, “Understanding Line Leak Detection Systems,” State Water Resources Control Board, California Environmental Protection Agency.
  2. Lee, T. S., 1993, “A Review on the Leak Detection System,” Daewoo Engineering & Construction Technology Magazine, Vol. 10, No. 1.
  3. Martin, M. T. and Doyle, J. F., 1996, “Impact Force Location in Frame Structures,” Int. J. Impact Engng, Vol. 18, No. 1, pp. 79-97. https://doi.org/10.1016/0734-743X(95)00016-9
  4. Lee, S. K., Banerjee, S. and Mal, A., 2007, “Identification of Impact Force on a Thick Plate Based on the Elastodynamic and Higher-Order Time-Frequency Analysis,” Journal of Mechanical Engineering Science, Vol. 221, No. 11, pp. 1249-1263. https://doi.org/10.1243/09544062JMES674
  5. Gao, Y., Muggleton, J. M., Brennan, M. J., Joseph, P. F. and Hunaidi O., 2005, “On the Selection of Acoustic/Vibration Sensors for Leak Detection in Plastic Water Pipes,” Journal of Sound and Vibration, Vol. 283, No. 3-5, pp. 927-941. https://doi.org/10.1016/j.jsv.2004.05.004
  6. Kim, M. S., Lee, S. K. and Kim, S. J., 2008, “Identification of Impact Force on the Gas Pipe Based on Analysis of the Acoustic Wave,” International Journal of Modern Physics B, Vol. 22, No. 9, pp. 1039-1044. https://doi.org/10.1142/S0217979208046281
  7. Kinsler, L. E., 1999, Fundamental of Acoustics 4th Edition, John Wiley & Sons, Inc., New York.
  8. Munjal, M. L., 1987, Acoustics of Ducts and Mufflers with Application to Exhaust and Ventilation System Design, Vibration Testing, John Wiley & Sons, Inc., New York.
  9. Eriksson, L. J., 1980, “Higher Order Mode Effects in Circular Order Mode Effects in Circular Ducts and Expansion Chamber,” Journal of Sound and Vibration, Vol. 68, No. 2, pp. 545-550.
  10. Mason, V., 1969, “Some Experiments on the Propagation of Sound along a Cylindrical Duct Containing Flowing Air,” Journal of Sound and Vibration, Vol. 10, No. 2, pp. 208-226. https://doi.org/10.1016/0022-460X(69)90197-7
  11. Beggs, H. D., 1991, Production Optimization, Oil & Gas Consultants International Inc., Vol.129.
  12. Kumar, S., 1987, Gas Production Engineering, Gulf Publishing Company, pp. 284-285.
  13. Burstein, L., Ingman, D. and Michlin, Y., 1999, “Correlation Between Gas Molecular Weight, Heating Value and Sonic Speed Under Variable Compositions of Natural Gas,” ISA Transactions, Vol. 38, pp. 347-359. https://doi.org/10.1016/S0019-0578(99)00028-2
  14. Lee, S. K., 2002, “An Acoustic Decay Measurement Based on Time-Frequency Analysis Using Wavelet Transform,” Journal of Sound and Vibration, Vol. 252, No. 1, pp. 141-152. https://doi.org/10.1006/jsvi.2001.4035
  15. Lee, S. K., 2007, “Acoustic and Noise Signal Processing and Its Application,” Journal of Sound and Vibration Magazine, Vol. 17, No. 1, pp. 9-15.