Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 51 3 2019 08 23 Leak detection, experimental and theoretical comparison of characteristics of transient flow in polyethylene pipelines Leak detection, experimental and theoretical comparison of characteristics of transient flow in polyethylene pipelines 547 556 2767 10.22060/ceej.2017.13539.5438 FA Mostafa Mirzaie Jeshni Department of Water Sciences Engineering, Shahid Chamran University Manoochehr Fathi-Moghadam Department of Water Sciences Engineering, Shahid Chamran University Alireza Sabet-imani Department of Water Sciences Engineering, Shahid Chamran University Asghar Akbari Department of Water Sciences Engineering, Shahid Chamran University Journal Article 2017 10 19 Polyethylene pipes are widely used in pressurized water systems. In the design and interpretation of the ram-trapped signal for diagnostic purposes, viscoelastic behavior of polyethylene tubes should be taken into account. The aim of this study is to detect leakage, and experimental and theoretical comparison of pressure wave velocity and over pressure of transient flow in polyethylene pipes with different Reynolds number. To achieve the objectives of this paper, a physical model was developed in laboratory of the Faculty of Water Sciences Engineering of Shahid Chamran University of Ahwaz and developed two different models of control and a leakage system was and were conducted a number of water-hammer tests. The leakage accuracy in this model increased with increase of Reynolds number. The highest and the lowest percent of the relative error for computational and experimental leakage were estimated 48.8% and 2.02% through a leak hole of 5 mm for experiments with Reynolds numbers of 1283 and 12974, respectively. Also, this inaccurate study shows the relationship between the theory of compressive velocity and overpressure in the polyethylene transfer pipes, so that the compressive velocity obtained from theoretical relationships is less than its actual value, as well as the relative error of the overpressure in leakage experiments Increasing the Reynolds number increases between the amount of the laboratory and the theory. Polyethylene pipes are widely used in pressurized water systems. In the design and interpretation of the ram-trapped signal for diagnostic purposes, viscoelastic behavior of polyethylene tubes should be taken into account. The aim of this study is to detect leakage, and experimental and theoretical comparison of pressure wave velocity and over pressure of transient flow in polyethylene pipes with different Reynolds number. To achieve the objectives of this paper, a physical model was developed in laboratory of the Faculty of Water Sciences Engineering of Shahid Chamran University of Ahwaz and developed two different models of control and a leakage system was and were conducted a number of water-hammer tests. The leakage accuracy in this model increased with increase of Reynolds number. The highest and the lowest percent of the relative error for computational and experimental leakage were estimated 48.8% and 2.02% through a leak hole of 5 mm for experiments with Reynolds numbers of 1283 and 12974, respectively. Also, this inaccurate study shows the relationship between the theory of compressive velocity and overpressure in the polyethylene transfer pipes, so that the compressive velocity obtained from theoretical relationships is less than its actual value, as well as the relative error of the overpressure in leakage experiments Increasing the Reynolds number increases between the amount of the laboratory and the theory. https://ceej.aut.ac.ir/article_2767_f75526659f31040afeb61cb7133e4e6d.pdf