Download or read book Leak Detection and Condition Assessment for Water Distribution Pipelines Using Fluid Transient Waves written by Jinzhe Gong and published by . This book was released on 2013 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The focus of this PhD research is to develop non-invasive and cost-effective techniques for assessing the structural condition of pressurised pipelines using fluid transient pressure waves. The specific objectives include the detection of leaks and localised deterioration that is distributed along a pipeline, such as extended sections of corrosion or the spalling of cement lining. The latter is described by pipeline condition assessment in this thesis. The transient behaviour of a leak is studied in the frequency domain. Numerical studies conducted in this research demonstrate that two leak-induced patterns (on the resonant and the anti-resonant responses) can exist in a frequency response diagram (FRD). The amplitudes of the responses are related to the impedance of the valve in a reservoir-pipeline-valve (RPV) system. A new leak detection technique has been developed in this research based on the further understanding of the leak-induced patterns. This technique uses the relative sizes of the first three resonant responses to determine the location and size of a single leak in RPV systems. In reservoir-pipeline-dead end systems, the information required for single event leak detection is further reduced to the first two resonant responses. A new measurement strategy for the extraction of the FRD of single pipelines is proposed in this research. The boundary valve loss is used to adjust the amplitude of the leak-induced pattern on the resonant responses and also the sharpness of the resonant peaks. A specific type of pseudo-random binary sequence (PRBS) termed the inverse repeat sequence (IRS), is used as the excitation signal. The antisymmetric property of IRS enables part of the nonlinear responses of the system under excitation to be cancelled out, yielding a measured FRD close to the theoretical linear system response. A side-discharge valve based transient generator is designed and fabricated in this research to implement the new FRD measurement strategy. Laboratory experiments are conducted on an intact pipeline and a pipeline with a leak. This research also conducts analysis of the characteristics of distributed pipe wall deterioration and develops new detection techniques. In a measured pressure trace, the size of the reflection resulting from a section of pipeline with a change in wall thickness is indicative of the characteristic impedance of this section. Once the impedance of this section is determined, the wave speed and wall thickness can be estimated. A technique for the detection of a single deteriorated section in pipelines is developed based on the above analysis. Two other condition assessment techniques are developed to deal with the complexities induced by multiple deteriorated sections. The first technique is termed reconstructive MOC (method of characteristics) analysis, which uses the pressure trace measured at the upstream face of the valve in a RPV system to determine the distribution of the impedance along the pipeline. The algorithm reconstructs a MOC grid by calculating the MOC compatibility equations backwards in time, estimating the properties of the pipeline (impedance, wave speed) and the length of each pipe reach as discretised by the MOC grid from the valve towards the reservoir. Preliminary experimental verification is conducted to verify the applicability of the new technique. The second technique is reconstructive transient analysis (RTA), which can be conducted at any interior accessible points along a pipeline, and does not require a RPV boundary condition. The RTA uses two pressure transducers in close proximity to measure two transient pressure traces in one test. A signal processing algorithm is developed to extract the directional transient waves (traveling upstream and downstream). The use of the directional transient waves enables the step response function (SRF) of the section of pipe upstream or downstream of the paired pressure transducers to be obtained. The reconstructive MOC analysis is then adapted to interpret the SRF to yield the distribution of the impedance, from which the location and severity of distributed deterioration can be identified." -- abstract, pages v-vi.

Download or read book Leak Detection written by Stuart Hamilton and published by IWA Publishing. This book was released on 2013-06-30 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ageing infrastructure and declining water resources are major concerns with a growing global population. Controlling water loss has therefore become a priority for water utilities around the world. In order to improve efficiencies, water utilities need to apply good practices in leak detection. Leak Detection: Technology and Implementation assists water utilities with the development and implementation of leak detection programs. Leak detection and repair is one of the components of controlling water loss. In addition, techniques are discussed within this book and relevant case studies are presented. The book provides useful and practical information on leakage issues.

Download or read book Leak Detection in Fluid Distribution Networks written by Abdulrahman Amin Alawadhi and published by . This book was released on 2019 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leakage is an undesired abnormality that causes economical losses and impacts the environment. Leak detection tests in pipe networks are usually interpreted using water-hammer equations (WHE). These equations are nonlinear hyperbolic partial differential equations (PDEs) used to describe transient flows in pipes. The associated uncertainties in initial and boundary conditions, parameters, and leak strength and location increases the stochastic behavior of these equations. The method of distributions is used to derive a deterministic PDE for probability density function (PDF) of pressure head and flow velocity under uncertain initial conditions. The derivation requires a closure approximation that ensures its consistency with the mean and the variance of the state variables. A series of numerical experiments confirms the computational gain of this method over Monte Carlo simulations. The PDF of pressure head obtained using the method of distributions serves as a prior PDF for data assimilation. Bayesian framework is used to update this distribution with a statistical model for observations obtained from the data collected by a pressure sensor. The result is posterior PDFs for leak location and leak strength. Series of numerical experiments are conducted for a single pipe and pipe networks under uncertain initial velocity and measurement noise to identify leak location and leak strength. The results are compared with the best fitness function that is used in inverse transient analysis.

Download or read book Leak Detection Methods for Plastic Water Distribution Pipes written by Osama Hunaidi and published by American Water Works Association. This book was released on 1999 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluates the effectiveness of pinpointing leaks in plastic pipe using acoustic leak detection equipment commonly used by the water industry in North America and promising technologies from other industries. Emphasizes technology and procedures for listening devices and an acoustic noise correlator. Research partner: National Research Council Canada.

Download or read book Verification and Control of Pressure Transients and Intrusion in Distribution Systems written by M. Friedman and published by International Water Assn. This book was released on 2005 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this project were to verify that

Download or read book Water Pipeline Condition Assessment written by Task Committee on Water Pipeline Committee Assessment and published by . This book was released on 2017 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: MOP 134 provides water utilities with an appropriate path for adequately determining the structural status of an individual transmission pipeline or pipeline system.

Download or read book Leak Detection Using Instantaneous Frequency Analysis written by Mohd Fairusham Ghazali and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Leaking pipes are a primary concern for water utilities around the globe as they compose a major portion of losses. Contemporary interest surrounding leaks is well documented and there is a proliferation of leak detection techniques. Although the reasons for these leaks are well known, some of the current methods for leak detection and location are either complicated, inaccurate and most of them are time consuming. Transient analyses offer a plausible route towards leak detection due to their robustness and simplicity. These approaches use the change of pressure response of the fluid in a pipeline to identify features. The method used in the current study employ a single pressure transducer to obtain the time domain signal of the pressure transient response caused by a sudden opening and closing of a solenoid valve. The device used is fitted onto a standard UK hydrant and both cause a pressure wave and acquire the pressure history. The work described here shows that the analysis using Hilbert transform (HT), Hilbert Huang transform (HHT) and EMD based method is a promising tool for leak detection and location in pipeline network. In the first part of the work, the analysis of instantaneous characteristics of transient pressure signal has been calculated using HT and HHT for both simulated and experimental data. These instantaneous properties of the signals are shown to be capable of detecting the reflection from the features of the pipe such as leakages and outlet. When tested with leak different locations, the processed results still show the existing of the features in the system. In the second part of the work, the study is based on newly method of analysing non-stationary data called empirical mode decomposition (EMD) for instantaneous frequency calculation for leak detection. First, the pressure signals were filtered in order to remove the noise using EMD. Then the instantaneous frequency was calculated and compared using different methods. With this method, it is possible to identify the leaks and also the features in the pipeline network. These were tested at different locations of a real water distribution system in the Yorkshire Water region.

Download or read book Leak Detection in Pipelines Using Hydraulic Transients written by Lennart Jönsson and published by . This book was released on 1997* with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Leak Detection in Pipelines Using Wavelet and Cepstrum Analysis written by Abdul Kadir Samta and published by . This book was released on 2013 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nowadays, piping system is one of the important features in either home of industrial user. It is essential for transporting fluid from a point to another point. But due to many reasons, leaks may occur in the pipelines. This research is focusing on detecting and locating the leaks in the pipeline and to successfully complete the research signal analysis of wavelet and cepstrum analysis is used. This research proposed a technique which is transient method. The basic principle is the fact that water spouting out of a leak in a pressurized pipe generates signal, and this signal contains information to whether a leak exists and where it is located. The present transient methods for finding leaks are mainly based upon correlation analysis, where one sensing device is installed at each side of a leak. This method is hard to operate because it needs a lot of operators to operate it due to equipment in different place. So to overcome this limitation, this research project proposed a new method by using just one sensing device which means all of the equipment in one place. This method use pressure transducer as the sensing device. This will make the method more friendly user and reduce the cost of operators. The results predict satisfactorily the leak location as the error between analyzed data and measured data is from 0.81% to 4.26%. This report starts with the introduction section to outline on the backgroundn and purpose of the study. It continues with the literature section that explains theleakage detection techniques, wave propagation and signal processing. The experimental part involves fabricating the pipe system using high density polyethylene and galvanized iron pipe. Subsequently signal processing section covers analysis of data and final results.

Download or read book Effects of Data Uncertainty on Pipeline Leak Detection Using Transient Flow Simulations written by Chʻun Tʻien and published by . This book was released on 1994 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Monitoring of Pipelines and Networks written by Cristina Verde and published by Springer. This book was released on 2018-08-02 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the analysis and design of advanced techniques for on-line automatic computational monitoring of pipelines and pipe networks. It discusses how to improve the systems’ security considering mathematical models of the flow, historical flow rate and pressure data, with the main goal of reducing the number of sensors installed along a pipeline. The techniques presented in the book have been implemented in digital systems to enhance the abilities of the pipeline network’s operators in recognizing anomalies. A real leak scenario in a Mexican water pipeline is used to illustrate the benefits of these techniques in locating the position of a leak. Intended for an interdisciplinary audience, the book addresses researchers and professionals in the areas of mechanical, civil and control engineering. It covers topics on fluid mechanics, instrumentation, automatic control, signal processing, computing, construction and diagnostic technologies.

Download or read book Improving Leak Detection in Water Distribution Networks Through Hydraulic Modeling and Pressure Management written by Noura Abu Al Faraj and published by . This book was released on 2012 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately six billion gallons of drinking water are lost through distribution systems every day across the United States. In Philadelphia alone, an estimated 22 million gallons per day (MGD) of water is unaccounted for. This constitutes 25% of drinking water produced each day. Water is lost through distribution networks due to various reasons, such as erroneous meter readings, inaccurate billing, and physical damage to the infrastructure. According to the Philadelphia Water Department's Water Audit, water losses in the year 2010 amounted to over $30 million. Not only does "unaccounted-for water" cost the city of Philadelphia millions of dollars every year, it could also be affecting the quality of our drinking water; undetected leaks could potentially allow pathogens to enter the pipes and contaminate the network's water. This risk is magnified in periods of high flow demands such as during fire emergencies. Currently, the City utilizes many methods for detecting and repairing leaks including acoustic leak detection methods. However, these methods are not fast and not very effective in large diameter pipes. This thesis proposes a method for leak detection that utilizes hydraulic modeling and pressure management in the water distribution network to find the source of leaks as quickly and efficiently as possible causing less water to be wasted. Millions of dollars worth of wasted water could be saved while protecting the quality of our water from contamination.

Download or read book Analysis and Design of an In pipe System for Water Leak Detection written by Dimitris M. Chatzigeorgiou and published by . This book was released on 2010 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leaks are a major factor for unaccounted water losses in almost every water distribution network. Pipeline leak may result, for example, from bad workmanship or from any destructive cause, due to sudden changes of pressure, corrosion, cracks, defects in pipes or lack of maintenance. The problem of leak becomes even more serious when it is concerned with the vital supply of fresh water to the community. In addition to waste of resources, contaminants may infiltrate into the water supply. The possibility of environmental health disasters due to delay in detection of water pipeline leaks have spurred research into the development of methods for pipeline leak and contamination detection. This thesis is on the analysis and design of a floating mobile sensor for leak detection in water distribution pipes. This work covers the study of two modules, namely a "floating body" along with its "sensing module". The Mobility Module or the floating body was carefully studied and designed using advanced CFD techniques to make the body as non-invasive to the flow as possible and to avoid signal corruption. In addition, experiments were carried out to investigate the effectiveness of using in-pipe measurements for leak detection in plastic pipes. Specifically, acoustic signals due to simulated leaks were measured and studied for designing a detection system to be deployed inside water networks of 100mm pipe size.

Download or read book Investigation of Factors Affecting Transient Pressure Wave Propagation and Implications to Transient Based Leak Detection Methods in Pipeline Systems written by Huanfeng Duan and published by . This book was released on 2011 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Pipeline Condition Assessment written by Utility Engineering and Surveying Institute (American Society of Civil Engineers). Task Committee on Water Pipeline Condition Assessment and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: MOP 134 provides water utilities with an appropriate path for adequately determining the structural status of an individual transmission pipeline or pipeline system.

Download or read book Pipeline Leak Detection written by Marcia Golmohamadi and published by . This book was released on 2015 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In the present research two techniques are applied for leak detection in pipelines. The first method is a hardware-based technique which uses ultrasonic wave's emission for pipeline inspection. Ultrasonic waves are propagated in the pipe walls and reflected signal from leakage will be used for pipe analysis. Several Pipes with various dimensions and characteristics are modeled by finite element method using ANSYS. Second order longitudinal modes of ultrasonic waves are emitted in their walls. For this purpose, excited frequency is calculated such that it excites the second order longitude mode. In order to investigate the behavior of emitted wave in contact with leakage, four sensors are used in outer surface of pipe. Waves are reflected when encountering leakage and the leak location is recognized knowing the wave emission speed and flight time of backscattered signals. Wavelet transform is used for processing these signals and recognizing leak location. This method is tested on several pipe models and it presents satisfactory results for short pipes. The second approach is a software-based method which works based on the transient model of the pipeline. In this method the outputs from simulated pipeline are compared to those measured from flow meters and if their difference goes beyond a threshold value, leak is detected. For leak localization a gradient pressure technique is applied which needs pressure slope measurements at inlet and outlet of the pipeline. Several cases with leak at various positions are studied. This method works well with high accuracy for long pipelines."--Abstract, page iii.

Download or read book Inverse Transient Analysis for Leak Detection and Calibration of Water Pipe Systems Modelling Special Dynamic Effects written by and published by . This book was released on 2003 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt: