Extended Blockage Detection in Pipelines by Using the System Frequency Response Analysis

Transient wave-blockage interaction and extended blockage detection in elastic water pipelines

“…Similarly, extended changes in pipe wall thickness and material was found to produce changes in the wavespeed in the laboratory studies of Hachem and Schleiss (2011, 2012aand 2012b and Tuck et al (2012). Duan et al (2012) and Tuck et al (2012) show that extended blockage changes the amplitude as well as the position of resonant responses from the system. An analytical expression for the blockage-induced changes in the system resonant frequencies was derived in Duan et al (2012) and was used for detecting extended blockages in pipelines.…”

“…Duan et al (2012) and Tuck et al (2012) show that extended blockage changes the amplitude as well as the position of resonant responses from the system. An analytical expression for the blockage-induced changes in the system resonant frequencies was derived in Duan et al (2012) and was used for detecting extended blockages in pipelines. To determine the properties of the blockage, an optimization process coupled with a Genetic Algorithm (GA) was used to fit the observed resonant frequencies with the theoretical expression.…”

“…The tenet of this approach is that a measured pressure wave signal in a conduit is modified by, and thus contains information on, the conduit properties. Stephens et al (2005), Brunone et al (2008) and Duan et al (2012) proposed that blockages in pipes are divided into two categories-discrete and extended blockages-according to its relative length to the total pipeline length. In the context of discrete blockages, Contractor (1965) shows that a discrete partial blockage causes a partial reflection of a waterhammer wave where the amplitude of the reflected wave provides information on the severity of the constriction and the arrival time of the reflected wave provides the location of the blockage.…”

“…Transient-based methods, where a transient signal is injected into the conduit and the response measured at specified locations, is a promising approach for detecting defects in pipes and have been used in the detection of discrete blockages, leaks, and assessment of pipe wall condition (Liggett and Chen, 1994, Brunone, 1999, Brunone and Ferrante, 2001, Vitkovsky et al, 2000, Wang et al, 2002, Wang et al, 2005, Ferrante and Brunone 2003, Covas et al, 2004, Mohapatra et al, 2006, Sattar et al, 2008, Lee et al, 2004, Lee et al, 2006, Lee et al, 2008, Stephens, 2008, Duan et al, 2011a, Duan et al, 2011b, Duan et al, 2012, Mohapatra and Chaudhry, 2011, Meniconi et al, 2009, Meniconi et al, 2011and Meniconi et al, 2013. The tenet of this approach is that a measured pressure wave signal in a conduit is modified by, and thus contains information on, the conduit properties.…”

Detection of Localized Deterioration Distributed along Single Pipelines by Reconstructive MOC Analysis

“…However, the structural complexity and parametric uncertainties of real pipes proved to be a serious obstacle to an efficient and accurate ITA. Duan et al (2012) proposed a technique for the detection of extended blockages by analyzing the frequency response of the pipeline system. Their analysis indicated that extended blockages can cause the resonant frequencies of the pipeline system to shift, and the locations and sizes of the blockages can be determined through an inverse calibration approach with optimization algorithms.…”