Management of water distribution systems in PDA conditions using isolation valves: case studies of real networks

Abstract The current paper reports on a case study investigating water distribution system management in emergency conditions when it is necessary to seal off a zone with isolation valves to allow repair. In these conditions, the pressure-driven analysis (PDA) is considered to be the most efficient approach for the analysis of a water distribution network (WDN), as it takes into account whether the head in a node is adequate to ensure service. The topics of this paper are innovative because, until now, previous approaches were based on the analysis of the network behaviour in normal conditions. In emergency conditions, it is possible to measure the reliable functioning of the system by defining an objective function (OF) that helps to choose the optimal number of additional valves in order to obtain adequate system control. The OF takes into account the new network topology by excluding the zone where the broken pipe is located. The results show that the solution did not improve significantly when the number of valves reached a threshold. The procedure applied to other real case studies seems to confirm the efficiency of the methodology even if further examination of other cases in different conditions is necessary

Identification of Measurement Points for Calibration of Water Distribution Network Models

AbstractMuch importance is given to determining the input data for water distribution system networks, particularly with regard to urban networks, because the design and the management of WDS are based on a verification model. Good calibration of models is required to obtain realistic results. This is possible by the use of a certain number of measurements: flow in pipes and pressure in nodes. The purpose of this paper is to analyze a new model able to provide guidance on the choice of measurement points to obtain the site data. All analyses are carried out firstly on literature networks and then on a real network using a new approach based on sensitivity matrices

Identification of leakages by calibration of WDS models

Open Access journalCopyright © 2013 The Authors. Published by Elsevier Ltd.12th International Conference on Computing and Control for the Water Industry, CCWI2013Leakage detection is critical for the proper management of water distribution systems (WDS). This paper proposes a leak detection approach based on a Bayesian calibration method. The methodology uses a newly formulated index, μ, which takes into account the variation of roughness in pipes between the calibrated models with and without leaks. Case studies, which use literature networks, are presented to demonstrate how the approach can be used in identifying pipes with losses. The approach starts with a calibration method followed by the analysis of sensitivity matrices. The approach proved to be effective in finding leaks, but the results depend crucially on the number and quality of the observed data.European CommissionEuropean Social FundRegion of Calabri

emergency management of water distribution systems the nodal demand control

Abstract During emergency situations (e.g., due to pipe bursts or other network failures), appropriate management of Water Distribution Systems (WDS) is required. Critical events often cause service failures, because the pressure head in some nodes of the network become inadequate to deliver required demand. In this paper, a new methodology is developed based on the nodal demand control. with the aim to increase the pressure head, and hence the flow rate actually delivered at critical nodes (i.e., hospitals, vulnerable customers, etc.). This is done to avoid or minimize service interruptions between the failure and the repair times. Furthermore, a pipe burst can cause isolation of a portion of the network such that the flow along pipes changes and this causes the reduction of head in some nodes. The proposed methodology is manages the delivered flow rate using a Pressure Driven Analysis (PDA) approach. This is based on operating control of valves and by identifying the nodes where the pressure control should be implemented. Those control nodes are chosen by the analysis of sensitivity matrices and the Max-Sum Method (Bush and Uber, 1998; Fiorini Morosini et al., 2014). The methodology is demonstrated on a case study for a real network of Cosenza, a town in the South of Italy

Model calibration as a tool for leakage identification in WDS: A real case study

16th Water Distribution System Analysis Conference, WDSA2014 — Urban Water Hydroinformatics and Strategic PlanningCopyright © 2014 The Authors. Published by Elsevier Ltd.Water leakage detection is important for a proper management of water distribution systems (WDS). This paper proposes the application of the leak detection approach based on a new Bayesian calibration methodology. The methodology uses a new developed index μ, which takes into account the difference in roughness values in pipes of the calibrated models with and without leaks. The case study is referred to a real network and is presented to demonstrate how the approach can be used in identifying pipes with losses. The approach starts with the UNINET calibration method followed by the analysis of sensitivity matrices. The case study proves that the approach is effective in finding leaks in real networks, but the results depend on the quality of the observed data

Emergency Management of Water Distribution Systems: The Nodal Demand Control

Abstract During emergency situations (e.g., due to pipe bursts or other network failures), appropriate management of Water Distribution Systems (WDS) is required. Critical events often cause service failures, because the pressure head in some nodes of the network become inadequate to deliver required demand. In this paper, a new methodology is developed based on the nodal demand control. with the aim to increase the pressure head, and hence the flow rate actually delivered at critical nodes (i.e., hospitals, vulnerable customers, etc.). This is done to avoid or minimize service interruptions between the failure and the repair times. Furthermore, a pipe burst can cause isolation of a portion of the network such that the flow along pipes changes and this causes the reduction of head in some nodes. The proposed methodology is manages the delivered flow rate using a Pressure Driven Analysis (PDA) approach. This is based on operating control of valves and by identifying the nodes where the pressure control should be implemented. Those control nodes are chosen by the analysis of sensitivity matrices and the Max-Sum Method (Bush and Uber, 1998; Fiorini Morosini et al., 2014). The methodology is demonstrated on a case study for a real network of Cosenza, a town in the South of Italy