Numerical modeling of pressure-reducing valves in water distribution network systems

1990 ◽  
Vol 17 (4) ◽  
pp. 547-557
Author(s):  
U. S. Panu

Computer models are no longer viewed as exotic luxuries, rather they are being increasingly accepted as necessities for effective planning and operation of water distribution systems. In large networks, pressure-reducing valves (PRVs) are common water appurtenances. However, through the use of the Hazen–Williams friction factor, there are difficulties in representing PRVs in network-analysis models. This paper focuses on these difficulties and suggests a procedure for resolving them through the use of modified Hazen–Williams friction factor. The effectiveness of the proposed modification in representing PRVs in the WATER model is demonstrated. Key words: network analysis, numerical modeling, hydraulics, municipal, water distribution, PRV representation, friction coefficient, Hazen–Williams, flow rate, simulations.

2011 ◽  
Vol 11 (4-5) ◽  
pp. 731-747 ◽  
Author(s):  
MASSIMILIANO CATTAFI ◽  
MARCO GAVANELLI ◽  
MADDALENA NONATO ◽  
STEFANO ALVISI ◽  
MARCO FRANCHINI

AbstractThis paper presents a new application of logic programming to a real-life problem in hydraulic engineering. The work is developed as a collaboration of computer scientists and hydraulic engineers, and applies Constraint Logic Programming to solve a hard combinatorial problem. This application deals with one aspect of the design of a water distribution network, i.e., the valve isolation system design. We take the formulation of the problem by Giustolisi and Savić (2008 Optimal design of isolation valve system for water distribution networks. InProceedings of the 10th Annual Water Distribution Systems Analysis Conference WDSA2008, J. Van Zyl, A. Ilemobade, and H. Jacobs, Eds.) and show how, thanks to constraint propagation, we can get better solutions than the best solution known in the literature for the Apulian distribution network. We believe that the area of the so-calledhydroinformaticscan benefit from the techniques developed in Constraint Logic Programming and possibly from other areas of logic programming, such as Answer Set Programming.


2012 ◽  
Vol 15 (3) ◽  
pp. 666-675 ◽  
Author(s):  
M. Ferrante ◽  
C. Massari ◽  
E. Todini ◽  
B. Brunone ◽  
S. Meniconi

In recent decades the hydraulics of leaks, i.e. the definition of the relationships linking the hydraulic quantities in pipes with leaks, has received increasing attention. On the one hand, the definition of the relationship between the leak outflow and the relevant parameters – e.g. the leak area and shape, the pressure inside the pipe and outside the leak, and the pipe material – is crucial for pressure control and inverse analysis techniques. On the other hand, if the effect of the leakage on the governing equations is not taken into account, i.e. the loss of the flow axial momentum is not considered, significant errors can be introduced in the simulation of water distribution systems. In this paper, the governing equations for a pipe with a leak are derived. The basic equations, obtained within different approaches, are presented in a consistent formulation and then compared with the results of some experimental tests. The leak jet angle and other major features of the results are analysed. The estimated values of the parameters can be used in the water distribution network models when pipes with a diffuse leakage are considered.


2019 ◽  
Vol 22 (4) ◽  
pp. 681-690 ◽  
Author(s):  
A. Fiorini Morosini ◽  
O. Caruso ◽  
P. Veltri

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.


2003 ◽  
Vol 3 (1-2) ◽  
pp. 307-312 ◽  
Author(s):  
M. Poulton

The deterioration of water distribution systems and the subsequent need for major rehabilitation has provided researchers with a challenge: to seek new techniques to facilitate decision-making and assist network planners. Consequently, a range of methods have been developed, concerning several key performance indicators. Those with the greatest potential tend to promote a pro-active approach to pipeline rehabilitation, by predicting future performance of individual or groups of pipes. Such an approach is essential if cost-effective solutions are to be found. Prediction models are based on indicators that are perceived to be the most appropriate for measuring and comparing an aspect of performance. The level of “appropriateness” is influenced not only by the availability of data and the ease at which it can be recorded, but also its accuracy and unambiguity. Consequently, indicators such as burst rates are widely used to assess structural performance. Ideally though, a more direct measure of the condition of a pipe could be used, such as its remaining wall thickness. This has previously been largely disregarded, due to the lack of appropriate (non-destructive) measurement technology. However, technological advances are being made to enable the inline monitoring of pipes and determination of deficiencies (particularly corrosion pits in cast iron pipes). This paper illustrates how online condition monitoring of distribution pipelines can be combined with existing prediction models, to facilitate the decision-making process. Integration is achieved through the use of a Geographical Information System (GIS), which greatly enhances representation of spatial and temporal information.


2021 ◽  
Vol 2139 (1) ◽  
pp. 012013
Author(s):  
C A Bonilla-Granados ◽  
N J Cely-Calixto ◽  
G A Carrillo Soto

Abstract Drinking-water distribution systems are generally designed with methodologies based on trial-and-error tests, which generate feasible results. However, these trials are not the most economical and reliable solution since they do not consider the optimization of the network. For the present work, the hydraulic model of the drinking water distribution network of San José de Cúcuta, Colombia, was optimized by applying the concept of resilience rate and minimum cost. The development of the work consisted of the hydraulic modeling of the physical components of the network in EPANET software, as well as the application of calculations of the connectivity coefficient and the unitary power of each section. With the data obtained from the modeling and calculations, the physical parameters were optimized, and the cost-benefit ratio was estimated. It was found that the current drinking water distribution system does not have a power surplus to overcome a system failure. The optimization increased the total energy surplus of the network (261%) and the resilience rate (585%). Also, the connectivity coefficient was improved with an average value of 0.95. The hydraulic optimization methodology applied resulted in a network resilient to system failures.


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