Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 51 5 2019 12 22 Sensitivity Analysis of Hydraulic Parameters on Contaminant Intrusion in Transient Conditions Sensitivity Analysis of Hydraulic Parameters on Contaminant Intrusion in Transient Conditions 907 924 2934 10.22060/ceej.2018.14230.5595 FA Milad Payesteh Msc graduated in Civil Engineering, Jundi-Shapur University of Technology, Dezful, Iran Alireza Keramat Faculty of Civil Engineering, Jondi Shapur University of Technology, Dezful, Iran 0000-0002-6280-4931 Journal Article 2018 03 18 Water quality degrades due to the complex physical, chemical and biological processes passing through the transmission lines. One of these widely attracted processes is contaminant intrusion due to a transient event. When the negative pressure wave of water hammer reaches a structural deteriorations such as a leakage, it can suddenly sucks pollution from the surrounding area of leakage to the main pipe flow which can in turn endanger public health. The purpose of this study is to determine the effect of hydraulic parameters on the duration of negative pressure and the magnitude of the negative pressure and subsequently the volume of contaminant intrusion, in the case of a simple reservoir-pipe[1]valve system with a leakage. In this study, the Eulerian approach using method of characteristics was used to model the transient flow. The total volume of contaminant parcel (VCPt) passing through the leakage to the main pipe flow is obtained from the Lagrangian solution of the advection equation. The results indicate that the volume of intrusion is dominated by the magnitude and duration of negative pressure at the leak. The intruded parcel is considered as a decisive criterion to compare various transient scenarios. Reservoir pressure head, fluid velocity inside the pipe, wave speed, pipe diameter, leak diameter and leakage location are respectively the most effective pipe and flow parameters on contaminant intrusion which their specific significance is investigated in this research. Investigation of the interaction of these factors in the volume of contaminant intrusion can be considered as a subject for future research. Water quality degrades due to the complex physical, chemical and biological processes passing through the transmission lines. One of these widely attracted processes is contaminant intrusion due to a transient event. When the negative pressure wave of water hammer reaches a structural deteriorations such as a leakage, it can suddenly sucks pollution from the surrounding area of leakage to the main pipe flow which can in turn endanger public health. The purpose of this study is to determine the effect of hydraulic parameters on the duration of negative pressure and the magnitude of the negative pressure and subsequently the volume of contaminant intrusion, in the case of a simple reservoir-pipe[1]valve system with a leakage. In this study, the Eulerian approach using method of characteristics was used to model the transient flow. The total volume of contaminant parcel (VCPt) passing through the leakage to the main pipe flow is obtained from the Lagrangian solution of the advection equation. The results indicate that the volume of intrusion is dominated by the magnitude and duration of negative pressure at the leak. The intruded parcel is considered as a decisive criterion to compare various transient scenarios. Reservoir pressure head, fluid velocity inside the pipe, wave speed, pipe diameter, leak diameter and leakage location are respectively the most effective pipe and flow parameters on contaminant intrusion which their specific significance is investigated in this research. Investigation of the interaction of these factors in the volume of contaminant intrusion can be considered as a subject for future research. https://ceej.aut.ac.ir/article_2934_5dc126b503e374b0e08231344a7f493f.pdf