Search results for "Water distribution Network"

Experimental Evidence of Leaks in Elastic Pipes

2016

Several studies have been carried out in recent decades to establish a relationship between total head and leaks. In literature, the leakage governing equations have been analysed in light of pipe materials, water head, leak dimension or shape. Most of these contributions questioned the classical Torricelli equation, demonstrating through experimental evidence that the classical orifice law can give unsatisfactory results. Nevertheless, starting from the Torricelli equation, other exponential or linear governing equations have been proposed as mathematical models able to reproduce the leakages in water distribution systems (WDSs). To investigate the validity of the proposed governing equati…

Leakage Detection via Edge Processing in LoRaWAN-based Smart Water Distribution Networks

2022

The optimization and digitalization of Water Distribution Networks (WDNs) are becoming key objectives in our modern society. Indeed, WDNs are typically old, worn and obsolete. These inadequate conditions of the infrastructures lead to significant water loss due to leakages inside pipes, junctions and nodes. It has been measured that in Europe the average value of lost water is about 26 %. Leakage control in current WDNs is typically passive, repairing leaks only when they are visible. Emerging Low Power Wide Area Network (LPWAN) technologies, and especially IoT ones, can help monitor water consumption and automatically detect leakages. In this context, LoRaWAN can be the right way to deploy…

Optimal Placement of Pressure Sensors Using Fuzzy DEMATEL-Based Sensor Influence

2020

[EN] Nowadays, optimal sensor placement (OSP) for leakage detection in water distribution networks is a lively field of research, and a challenge for water utilities in terms of network control, management, and maintenance. How many sensors to install and where to install them are crucial decisions to make for those utilities to reach a trade-off between efficiency and economy. In this paper, we address the where-to-install-them part of the OSP through the following elements: nodes' sensitivity to leakage, uncertainty of information, and redundancy through conditional entropy maximisation. We evaluate relationships among candidate sensors in a network to get a picture of the mutual influenc…

A numerical unsteady friction model for the transient flow arising during the filling process of intermittent water distribution systems.

2011

Managing expert knowledge in water network expansion project implementation

2021

[EN] The implementation of expansion projects of water networks supplying growing cities is deemed to be a complex decision-making problem involving both technical aspects and expert knowledge. Management and control processes must rely on experts in the field whose know-how must be coupled with techniques able to deal with the natural subjectivity that affects input evaluations. Given the presence of many decision-making elements, the choice of proper hydraulic technical parameters may be linked to the main aspects of analysis requiring formal expert evaluation. In this contribution, the simulation of hydraulic indicators is integrated with a multi-criteria approach able to eventually dete…

Comparison between Entropy and Resilience as Indirect Measures of Reliability in the Framework of Water Distribution Network Design

2014

Abstract The aim of this paper is to investigate which between the entropy and resilience indices represents a better indirect measure of reliability in the framework of water distribution network design. The methodology adopted consisted of (a) multi-objective optimizations performed in order to minimize costs and maximize reliability, expressed by means of one of the indirect indices at time; (b) retrospective performance assessment of the solutions of Pareto fronts obtained. Two case studies of different topological complexity were considered. Results showed that indices based on energetic concepts (resilience and modified resilience) represent a better compact estimate of reliability th…

Impeller optimization in crossflow hydraulic turbines

2021

Crossflow turbines represent a valuable choice for energy recovery in aqueducts, due to their constructive simplicity and good efficiency under variable head jump conditions. Several experimental and numerical studies concerning the optimal design of crossflow hydraulic turbines have already been proposed, but all of them assume that structural safety is fully compatible with the sought after geometry. We show first, with reference to a specific study case, that the geometry of the most efficient impeller would lead shortly, using blades with a traditional circular profile made with standard material, to their mechanical failure. A methodology for fully coupled fluid dynamic and mechanical …

Definition of performance indicators for urban water distribution systems in drought conditions

2008

WATER DISTRIBUTION NETWORKS REHABILITATION BASED ON A SMALL INFORMATION DATASET

2012

A model of the filling process of an intermittent distribution network

2010

In many countries, private tanks are acquired by users to reduce their vulnerability to intermittent supply. The presence of these local reservoirs modifies the user demand pattern and usually increases user water demand at the beginning of the service period depending on the tank filling process. This practice is thus responsible for the inequality that occurs among users: those located in advantaged positions of the network are able to obtain water resources soon after the service period begins, while disadvantaged users have to wait much longer, after the network is full. This dynamic process requires the development of ad hoc models in order to obtain reliable results. This paper discus…