scholarly journals Average Operating Pressure Effect on Water Supply Systems Performances. A Case Study for 12 Romanian Small Water Distribution Networks

2021 ◽  
Vol 11 (2) ◽  
pp. 143-150
Author(s):  
E. Vitan ◽  
Anca Hotupan ◽  
Adriana Hadarean

Abstract The performance evaluation of an implemented water distribution network is in tight relation with the choice of adequate measures for water loss reduction. Hence, the consequences of placing the water network in a wrong performance category are bad and will conduct to unreasonably costs or considerable water loss volumes. Therefore, the evaluation of the water network performance level based on both Non-Revenue Water (NRW) and Infrastructure Leakage Index (ILI) indicators is to be recommended. This paper deals with the performance evaluation of water distribution systems based on the calculated performance indicators NRW and ILI. For this purpose, collected data for a period of one year from 12 Romanian small water distribution systems and two simplified average pressure determination methods were used.

2021 ◽  
Author(s):  
KEZHEN RONG ◽  
Minglei Fu ◽  
JIAWEI CHEN ◽  
LEJIN ZHENG ◽  
JIANFENG ZHENG ◽  
...  

Abstract Water distribution systems (WDSs) are used to transmit and distribute water resources in cities. Water distribution networks (WDNs) are partitioned into district metered areas (DMAs) by water network partitioning (WNP), which can be used for leak control, pollution monitoring, and pressure optimization in WDS management. In order to overcome the limitations of optimal search range and the decrease of recovery ability caused by two-step WNP and fixed DMAs in previous studies, this study developed a new method combining a graph neural network to realize integrated WNP and dynamic DMAs to optimize WDS management and respond to emergencies. The proposed method was tested in a practical case study; the results showed that good hydraulic performance of the WDN was maintained and that dynamic DMAs demonstrated excellent stability in emergency situations, which proves the effectiveness of the method in WNP.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2447
Author(s):  
Gideon Johannes Bonthuys ◽  
Marco van Dijk ◽  
Giovanna Cavazzini

Excess pressure within water distribution systems not only increases the risk for water losses through leakages but provides the potential for harnessing excess energy through the installation of energy recovery devices, such as turbines or pump-as-turbines. The effect of pressure management on leakage reduction in a system has been well documented, and the potential for pressure management through energy recovery devices has seen a growth in popularity over the past decade. Over the past 2 years, the effect of energy recovery on leakage reduction has started to enter the conversation. With the theoretical potential known, researchers have started to focus on the location of energy recovery devices within water supply and distribution systems and the optimization thereof in terms of specific installation objectives. Due to the instrumental role that both the operating pressure and flow rate plays on both leakage and potential energy, daily variation and fluctuations of these parameters have great influence on the potential energy recovery and subsequent leakage reduction within a water distribution system. This paper presents an enhanced optimization procedure, which incorporates user-defined weighted importance of specific objectives and extended-period simulations into a genetic algorithm, to identify the optimum size and location of potential installations for energy recovery and leakage reduction. The proposed procedure proved to be effective in identifying more cost-effective and realistic solutions when compared to the procedure proposed in the literature.


Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1352 ◽  
Author(s):  
Cao ◽  
Hopfgarten ◽  
Ostfeld ◽  
Salomons ◽  
Li

Many studies on pressure sensor (PS) placement and pressure reducing valve (PRV) localization in water distribution systems (WDSs) have been made with the objective of improving water leakage detection and pressure reduction, respectively. However, due to varying operation conditions, it is expected to realize pressure control using a number of PSs and PRVs to keep minimum operating pressure in real-time. This study aims to investigate the PS placement and PRV localization for the purpose of pressure control system design for WDSs. For such a control system, a PS should be positioned to represent the pressure patterns of a region of the WDS. Correspondingly, a PRV should be located to achieve a maximum pressure reduction between two neighboring regions. According to these considerations, an approach based on the k-means++ method for simultaneously determining the numbers and positions of both PSs and PRVs is proposed. Results from three case studies are presented to demonstrate the effectiveness of the suggested approach. It is shown that the sensors positioned have a high accuracy of pressure representation and the valves localized lead to a significant pressure reduction.


2007 ◽  
Vol 56 (9) ◽  
pp. 29-36 ◽  
Author(s):  
M. Möderl ◽  
T. Fetz ◽  
W. Rauch

A traditional procedure for performance evaluation of systems is to test approaches on one or more case studies. However, it is well known that the investigation of real case studies is a tedious task. Moreover, due to the limited amount of case studies available it is not certain that all aspects of a problem can be covered in such procedure. With increasing computer power an alternative methodology has emerged, that is the investigation of a multitude of virtual case studies by means of a stochastic consideration of the overall performance. Within the frame of this approach we develop here a modular design system (MDS) for water distribution systems (WDSs). With the algorithmic application of such a MDS it is possible to create a variety of different WDSs. As an example of stochastic performance evaluation the impact of pipe breakages on WDSs is estimated applying a pressure driven performance indicator. This performance indicator is evaluated stochastically. Likewise the performance evaluation of a variety of WDSs is also performed stochastically. Cumulative distribution function, histogram and other statistical properties of 2,280×1,000 performance results of the different WDSs are calculated to highlight the applicability of the introduced stochastic approach.


2008 ◽  
Vol 10 (4) ◽  
pp. 267-274 ◽  
Author(s):  
Ami Preis ◽  
Avi Ostfeld

Following the events of 9/11/2001 in the US, the world public awareness to possible terrorist attacks on water supply systems has increased significantly. The security of drinking water distribution systems has become a foremost concern around the globe. Water distribution systems are spatially diverse and thus are inherently vulnerable to intentional contamination intrusions. In this study, a multiobjective optimization evolutionary model for enhancing the response against deliberate contamination intrusions into water distribution systems is developed and demonstrated. Two conflicting objectives are explored: (1) minimization of the contaminant mass consumed following detection, versus (2) minimization of the number of operational activities required to contain and flush the contaminant out of the system (i.e. number of valves closure and hydrants opening). Such a model is aimed at directing quantitative response actions in opposition to the conservative approach of entire shutdown of the system until flushing and cleaning is completed. The developed model employs the multiobjective Non-Dominated Sorted Genetic Algorithm–II (NSGA-II) scheme, and is demonstrated using two example applications.


2014 ◽  
Vol 6 (4) ◽  
pp. 444-450 ◽  
Author(s):  
Mindaugas Rimeika ◽  
Anželika Jurkienė

The main performance indicators of a water supply system include the quality and safety of water, continuous work, relevant pressure and small water loss. The majority of foreign and local projects on reducing water loss have been carried out in the water supply systems of metropolitans; however, the specificity of small settlements differs from that of big cities. Differences can be observed not only in the development of infrastructure and technical indicators but also in the features of water consumption. The article presents the analysis of water loss formation and describes reduction measures in a small settlement. The conducted research defines that water loss in big cities is much smaller than that in small settlements. The major part of water used in small settlements is applied for agrarian purposes rather than for domestic needs. It has been found that water is employed for the irrigation of plants and livestock watering, which often is not accounted. Research also shows that slight (<0.2 m³/h) physical water loss (holes in the network) that occur in small settlements may compose up to 30% of all water supplied to the water network. Pagrindiniai vandens tiekimo sistemos efektyvumo rodikliai yra šie: vandens saugumas ir kokybė, nepertraukiamas darbas, tinkamas slėgis ir maži vandens nuostoliai. Absoliuti dauguma užsienio ir šalies vandens nuostolių mažinimo projektų buvo atlikta didmiesčių vandentiekiuose, tačiau mažų gyvenviečių specifika gerokai skiriasi nuo didžiųjų miestų. Skiriasi ne tik infrastruktūros lygis, techniniai rodikliai, bet ir vandens vartojimo ypatumai. Straipsnyje analizuojami vandens nuostolių susidarymas ir galimi mažinimo būdai mažose gyvenvietėse. Nustatyta, kad rajono centruose susidarantys vandens nuostoliai yra gerokai mažesni nei mažose gyvenvietėse. Didžioji dalis gyvenvietėse vartojamo vandens skirta augalams laistyti ir gyvuliams girdyti, o ne gyventojų buitiniams poreikiams tenkinti. Nustatyta, kad vanduo, naudojamas laistyti ir gyvuliams girdyti, dažnai nėra įtraukiamas į apskaitą. Nustatyta, kad mažų gyvenviečių vandentiekio tinkle susidarantys maži (<0,2 m³/h) fiziniai nuostoliai (pvz., dėl skylių tinkle), gali sudaryti daugiau nei 30 % viso į tinklą tiekiamo vandens kiekio.


2020 ◽  
Author(s):  
Riccardo Taormina ◽  
Mohammad Ashrafi ◽  
Andres Murillo ◽  
Stefano Galelli

<p><span>Simulation-based optimization is widely used for designing and managing water distribution networks. The process involves the use of accurate computational models, such as EPANET, which represent the physical processes taking place in the water network and reproduce the control logic governing its operations. Unfortunately, running such models requires expensive computations, which, in turn, may hinder the application of simulation-based optimization to large and complex problems. This issue can be overcome by resorting to surrogate models, that is, simplified data-driven models that accurately mimic the behaviours of physical-based models at a fraction of the computational costs. In this work, we explore the potential of Deep Learning Neural Networks (DLNN) for building surrogate models for water distribution systems. Different DLNN architectures, including feed-forward and recurrent neural networks, are trained and validated on datasets generated through EPANET simulations. The DLNN models are then used in lieu of the original EPANET model to speed-up the evaluation of the objective function employed in a simulation-based optimization problem. The effectiveness of the proposed technique is assessed on a realistic case-study involving cyber-attacks on a water network. In particular, the DLNN surrogate models are employed by an evolutionary optimization algorithm that schedules the operations of hydraulic actuators in order to best respond to the attacks and facilitate the recovery process.</span></p>


2014 ◽  
Vol 17 (1) ◽  
pp. 20-35 ◽  
Author(s):  
João Marques ◽  
Maria Cunha ◽  
Dragan A. Savić

This paper presents a real options approach to handling uncertainties associated with the long-term planning of water distribution system development. Furthermore, carbon emissions associated with the installation and operation of water distribution networks are considered. These emissions are computed by taking an embodied energy approach to the different materials used in water networks. A simulated annealing heuristic is used to optimise a flexible eco-friendly design of water distribution systems for an extended life horizon. This time horizon is subdivided into different time intervals in which different possible decision paths can be followed. The proposed approach is applied to a case study and the results are presented according to a decision tree. Lastly, some comparisons and results are used to demonstrate the quality of the results of this approach.


1988 ◽  
Vol 78 (2) ◽  
pp. 317-328 ◽  
Author(s):  
P. H. Langton ◽  
P. S. Cranston ◽  
P. Armitage

AbstractChironomid midges have been known to include parthenogenetic species for over a century. One of these species, Paratanytarsus grimmii (Schneider), cited under several different names here shown to be junior synonyms, has attained some notoriety as a pest. Its occurrence as a supposedly paedogenetic (actually pharate adult parthenogenetic) inhabitant of water distribution systems is discussed and related to its more usual occurrence in a variety of small water bodies including aquaria. New synonymy is proposed and a lectotype designated.


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