scholarly journals Pressure-driven modelling of water distribution systems

2003 ◽  
Vol 3 (1-2) ◽  
pp. 255-261 ◽  
Author(s):  
T. Tanyimboh ◽  
B. Tahar ◽  
A. Templeman
Keyword(s):  
Distribution Systems ◽  
Water Distribution ◽  
Line Search ◽  
Water Distribution Systems ◽  
Operating Conditions ◽  
Governing Equations ◽  
Novel Method ◽  
Newton Raphson ◽  
Abnormal Operating Conditions ◽  
Demand Driven Analysis

This paper presents a novel method to model water distribution systems (WDS) with insufficient pressure. Methods for the prediction of the performance of a WDS with pressure deficiencies are reviewed. The influence of imposed relationships between nodal heads and outflows is assessed and numerical results are given. A Newton-Raphson technique plus line search is employed for solving the governing equations. It is demonstrated that the approach offers superior results for the hydraulic performance of networks under abnormal operating conditions compared to demand-driven analysis-based models.

scholarly journals Modeling Bacterial Regrowth and Trihalomethane Formation in Water Distribution Systems

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 463
Author(s):  
Gopinathan R. Abhijith ◽  
Leonid Kadinski ◽  
Avi Ostfeld
Keyword(s):  
Distribution Systems ◽  
Water Distribution ◽  
Mechanistic Model ◽  
Water Distribution Systems ◽  
Sensitivity Study ◽  
Operating Conditions ◽  
Growth Rate Constant ◽  
Model Parameters ◽  
Bacterial Regrowth ◽  
The Impact

The formation of bacterial regrowth and disinfection by-products is ubiquitous in chlorinated water distribution systems (WDSs) operated with organic loads. A generic, easy-to-use mechanistic model describing the fundamental processes governing the interrelationship between chlorine, total organic carbon (TOC), and bacteria to analyze the spatiotemporal water quality variations in WDSs was developed using EPANET-MSX. The representation of multispecies reactions was simplified to minimize the interdependent model parameters. The physicochemical/biological processes that cannot be experimentally determined were neglected. The effects of source water characteristics and water residence time on controlling bacterial regrowth and Trihalomethane (THM) formation in two well-tested systems under chlorinated and non-chlorinated conditions were analyzed by applying the model. The results established that a 100% increase in the free chlorine concentration and a 50% reduction in the TOC at the source effectuated a 5.87 log scale decrement in the bacteriological activity at the expense of a 60% increase in THM formation. The sensitivity study showed the impact of the operating conditions and the network characteristics in determining parameter sensitivities to model outputs. The maximum specific growth rate constant for bulk phase bacteria was found to be the most sensitive parameter to the predicted bacterial regrowth.

A New Energy Optimization Strategy for Pumping Operation in Water Distribution Systems

2012 ◽  
Author(s):  
Dhafar Al-Ani ◽  
Saeid Habibi
Keyword(s):  
Distribution System ◽  
Energy Cost ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution System ◽  
Water Distribution Systems ◽  
Energy Optimization ◽  
Operating Conditions ◽  
Optimization Strategy ◽  
Multi Objective

As time goes on, more and more operating-modes based on changing demand profiles will be compiled to enrich the range of feasible solutions for a water distribution system. This implies the conservation of energy consumed by a water pumping station and improves the ability for energy optimization. Another important goal was improving safety, reliability, and maintenance cost. In this paper, three important goals were addressed: cost-effectives, safety, and self-sustainability operations of water distribution systems. In this work, the objective functions to optimize were total electrical energy cost, maintenance costs, and reservoir water level variation while preserving the service provided to water clients. To accomplish these goals, an effective Energy Optimization Strategy (EOS) that manages trade-off among operational cost, system safety, and reliability was proposed. Moreover, the EOS aims at improving the operating conditions (i.e., pumping schedule) of an existing network system (i.e., with given capacities of tanks) and without physical changes in the infrastructure of the distribution systems. The new strategy consisted of a new Parallel Multi-objective Particle Swarm optimization with Adaptive Search-space Boundaries (P-MOPSO-ASB) and a modified EPANET. This has several advantages: obtaining a Pareto-front with solutions that are quantitatively equally good and providing the decision maker with the opportunity to qualitatively compare the solutions before their implementation into practice. The multi-objective optimization approach developed in this paper follows modern applications that combine an optimization algorithm with a network simulation model by using full hydraulic simulations and distributed demand models. The proposed EOS was successfully applied to a rural water distribution system, namely Saskatoon West. The results showed that a potential for considerable cost reductions in total energy cost was achieved (approximately % 7.5). Furthermore, the safety and the reliability of the system are preserved by using the new optimal pump schedules.

scholarly journals Modeling the Formation and Propagation of 2,4,6-trichloroanisole, a Dominant Taste and Odor Compound, in Water Distribution Systems

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 638
Author(s):  
Gopinathan R. Abhijith ◽  
Avi Ostfeld
Keyword(s):  
Enzymatic Activity ◽  
Reactive Transport ◽  
Distribution Systems ◽  
Water Distribution ◽  
Formation Rate ◽  
Critical Role ◽  
Water Distribution Systems ◽  
Operating Conditions ◽  
Effect Of Temperature ◽  
Taste And Odor

2,4,6-trichloroanisole (2,4,6-TCA) formation is often reported as a cause of taste and odor (T&O) problems in water distribution systems (WDSs). The biosynthesis via microbial O-methylation of 2,4,6-trichlorophenol (2,4,6-TCP) is the dominant formation pathway in distribution pipes. This paper attempted to utilize the reported data on the microbial O-methylation process to formulate deterministic kinetic models for explaining 2,4,6-TCA formation dynamics in WDSs. The pipe material’s critical role in stimulating O-methyltransferases enzymatic activity and regulating 2,4,6-TCP bioconversion in water was established. The kinetic expressions formulated were later applied to develop a novel EPANET-MSX-based multi-species reactive-transport (MSRT) model. The effects of operating conditions and temperature in directing the microbiological, chemical, and organoleptic quality variations in WDSs were analyzed using the MSRT model on two benchmark systems. The simulation results specified chlorine application’s implication in maintaining 2,4,6-TCA levels within its perception limit (4 ng/L). In addition, the temperature sensitivity of O-methyltransferases enzymatic activity was described, and the effect of temperature increase from 10 to 25 °C in accelerating the 2,4,6-TCA formation rate in WDSs was explained. Controlling source water 2,4,6-TCP concentration by accepting appropriate treatment techniques was recommended as the primary strategy for regulating the T&O problems in WDSs.

Modelling bacteriological water quality in drinking water distribution systems

1998 ◽  
Vol 38 (8-9) ◽  
pp. 299-307 ◽  
Author(s):  
P. Piriou ◽  
S. Dukan ◽  
L. Kiene
Keyword(s):  
Drinking Water ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Bulk Water ◽  
Operating Conditions ◽  
Bacterial Counts ◽  
Drinking Water Distribution Systems ◽  
Biofilm Detachment ◽  
Drinking Water Distribution

Because on-site experimentation raises numerous problems, the study and the modelling of bacterial regrowth phenomena in drinking water distribution systems has been performed using a pipe loop pilot under various operating conditions. As a result, experiments have shown that inlet bacterial counts have little influence on the biofilm behavior which is mainly driven by the amount of available nutrients (BDOC). Biofilm detachment has a significant influence on the increase of suspended bacterial counts with time in relation to the net growth in the bulk water. All these results have been used to develop and validate a deterministic type of model, called PICCOBIO. Some guidelines to achieve water bacteriological stability have been proposed using model simulations.

scholarly journals Qualification of Hydraulic Analysis Models for Optimal Design of Water Distribution Systems

2021 ◽  
Vol 11 (17) ◽  
pp. 8152
Author(s):  
Young Hwan Choi
Keyword(s):  
Optimal Design ◽  
Negative Pressure ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Real Life ◽  
Operating Conditions ◽  
Design Model ◽  
Hydraulic Analysis ◽  
Design Characteristics

The hydraulic analysis of water distribution systems (WDSs) is divided into two approaches, namely, a demand-driven analysis (DDA) and a pressure-driven analysis (PDA). In DDA, the basic assumption is that the nodal demand is fully supplied irrespective of the nodal pressure, which is mainly suitable for normal operating conditions. However, in abnormal conditions, such as pipe failures or unexpected increases in demand, the DDA approach may cause unrealistic results, such as negative pressure. However, despite these realistic hydraulic analysis approaches for WDSs being emphasized in the design process, this consideration was lacking in the design aspect. Therefore, in this study, the designs by the DDA-based design model and PDA-based design model are compared, and their design characteristics are analyzed to identify the efficiency of the WDSs design under abnormal system conditions. The developed PDA model was applied to three networks (a well-known benchmark system and a real-life WDN), and the results showed that the proposed model is superior to other reported models when dealing with negative pressure under abnormal conditions. In addition, the optimal design of WDN considered PDA is presented, and the optimal construction cost is decreased to increase the percentage of PDA.

scholarly journals Real-time neuro-fuzzy controller for pressure adjustment in water distribution systems

2020 ◽  
Author(s):  
Hugo Augusto Marinho Moreira ◽  
Heber Pimentel Gomes ◽  
Juan Moises Mauricio Villanueva ◽  
Saulo de Tarso Marques Bezerra
Keyword(s):  
Real Time ◽  
Distribution Systems ◽  
Water Distribution ◽  
Fuzzy Controller ◽  
Water Distribution Systems ◽  
Operating Conditions ◽  
The Other ◽  
Pumping System ◽  
Neuro Fuzzy ◽  
Demand Variation

Abstract This work applied a neuro-fuzzy technique for real-time pressure control in water distribution systems with variable demand. The technique acted to control the rotation speed of the pumping system, aiming mainly at increasing energy efficiency. Fuzzy, neural and neuro-fuzzy controllers were tested in an experimental setup to compare their performances in a transient regime, a permanent regime, and with respect to disturbances applied to the system. To evaluate the efficiency of the system, a demand variation curve was emulated for different operating conditions. The results demonstrate that the neuro-fuzzy controller (NFC) presented a significant increase in pumping system efficiency and a reduction in specific energy consumption of up to 392% when compared to the other controllers. Target pressures were kept close to the set-point values with low hydraulic transients and maintained satisfactory stability (error <8%) under severe situations of demand variation. It is concluded that the NFC presented superior results when compared with the other analyzed controllers.

An Ontological Approach to Water Distribution Systems Management

WRPMD'99 ◽  
1999 ◽  
Author(s):  
P. Costa ◽  
A. Esposito ◽  
C. Gualtieri ◽  
D. Pianese ◽  
G. Pulci Doria ◽  
...  
Keyword(s):  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
Systems Management ◽  
Ontological Approach

Robust Estimation of Integrated Hydraulics and Parameters in Water Distribution Systems

2001 ◽  
Author(s):  
Mietek A. Brdys ◽  
Kazimierz Duzinkiewicz ◽  
Michal Grochowski ◽  
Tomasz Rutkowski
Keyword(s):  
Robust Estimation ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems
Sign in / Sign up

Export Citation Format

Share Document