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In water distribution networks, the adjustment of the driving curves of pumping systems to the setpoint curves allows for determining the minimum energy cost that can be achieved in terms of pumping. This paper presents the methodology for calculating the optimal setpoint curves in water networks with multiple pumping systems, pressure dependent and independent consumption, with and without storage capacity. In addition, the energy and cost implications of the setpoint curve are analyzed. Three objective functions have been formulated depending on the case study, one of minimum energy and two of costs that depend on whether or not the presence of storage tanks is considered. For the optimization process, two algorithms have been used, Hooke and Jeeves and differential evolution. There are two study networks: TF and Richmond. The results show savings of close to 10% in the case of the Richmond network. [ABSTRACT FROM AUTHOR]

The optimal function of a water distribution network is reached when the consumer demands are satisfied using the lowest quantity of energy, maintaining the minimal pressure required at the same time. One way to achieve this is through optimization of flow rate injection based on the use of the setpoint curve concept. In order to obtain that, a methodology is proposed. It allows for the assessment of the flow rate and pressure head that each pumping station has to provide for the proper functioning of the network while the minimum power consumption is kept. The methodology can be addressed in two ways: the discrete method and the continuous method. In the first method, a finite set of combinations is evaluated between pumping stations. In the continuous method, the search for the optimal solution is performed using optimization algorithms. In this paper, Hooke-Jeeves and Nelder-Mead algorithms are used. Both the hydraulics and the objective function used by the optimization are solved through EPANET and its Toolkit. Two case studies are evaluated, and the results of the application of the different methods are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a modified Shuffled Frog Leaping Algorithm (SFLA) applied to the design of water distribution networks. Generally, one of the major disadvantages of the traditional SFLA is the high number of parameters that need to be calibrated for proper operation of the algorithm. A method for calibrating these parameters is presented and applied to the design of three benchmark medium-sized networks widely known in the literature (Hanoi, New York Tunnel, and GoYang). For each of the problems, over 35,000 simulations were conducted. Then, a statistical analysis was performed, and the relative importance of each of the parameters was analyzed to achieve the best possible configuration of the modified SFLA. The main conclusion from this study is that not all of the original SFL algorithm parameters are important. Thus, the fraction of frogs in the memeplex q can be eliminated, while the other parameters (number of evolutionary steps Ns, number of memeplexes m, and number of frogs n) may be set to constant values that run optimally for all medium-sized networks. Furthermore, the modified acceleration parameter C becomes the key parameter in the calibration process, vastly improving the results provided by the original SFLA. [ABSTRACT FROM AUTHOR]

Pumping station (PS) designs in water networks basically contemplate technical and economic aspects. Technical aspects could be related to the number of pumps in PS and the operational modes of PS. Meanwhile, economic aspects could be related to all the costs that intervene in a PS design, such as investment, operational and maintenance costs. In general, water network designs are usually focused on optimizing operational costs or investment costs, However, some subjective technical aspects have not been approached, such as determining the most suitable pump model, the most suitable number of pumps and the complexity of control system operation in a PS design. Therefore, the present work aims to select the most suitable pump model and determine the priorities that technical and economic factors could have in a PS design by a multi-criteria analysis, such as an analytic hierarchy process (AHP). The proposed work will contemplate two main criteria, and every criterion will be integrated by sub-criteria to design a PS. In this way, technical factors (number of pumps and complexity of the operating system) and economic factors (investment, operational and maintenance costs) will be considered for a PS design. The proposed methodology consists of realizing surveys to a different group of experts that determines the importance of one criterion over each other criterion in a PS design through pairwise comparisons. Finally, this methodology will provide importance weight for the criteria and sub-criteria on the PS. Besides, this work will perform a rating of the considered alternatives of pump models in every case study, evaluating quantitatively every alternative with every criterion in the PS design. The main objective of this work will select the most adequate pump model according to the obtained rating, considering technical and economic aspects in every case study. [ABSTRACT FROM AUTHOR]

A problem for drainage systems managers is the increase in extreme rain events that are increasing in various parts of the world. Their occurrence produces hydraulic overload in the drainage system and consequently floods. Adapting the existing infrastructure to be able to receive extreme rains without generating consequences for cities' inhabitants has become a necessity. This research shows a new way to improve drainage systems with minimal investment costs, using for this purpose a novel methodology that considers the inclusion of hydraulic control elements in the network, the installation of storm tanks and the replacement of pipes. The presented methodology uses the Storm Water Management Model for the hydraulic analysis of the network and a modified Genetic Algorithm to optimize the network. In this algorithm, called the Pseudo-Genetic Algorithm, the coding of the chromosomes is integral and has been used in previous studies of hydraulic optimization. This work evaluates the cost of the required infrastructure and the damage caused by floods to find the optimal solution. The main conclusion of this study is that the inclusion of hydraulic controls can reduce the cost of network rehabilitation and decrease flood levels. [ABSTRACT FROM AUTHOR]

The control system's point is to bring the pumping curve close to the set-point curve. That concept is essential for proper design of a pumping station. An adequate design is focused not only on selecting the total number of pumps and the type of control to use (flow or pressure), but it also is important to determine the optimal number of fixed speed pumps (FSPs) and variable speed pumps (VSPs) for each flow rate. This work discusses the most common methods and procedures for control systems on a design of pumping stations with a proposed methodology. This methodology consists of expressing the characteristics of the pumping curve and the set-point curve in a dimensionless form so that the methodology is standardized for any pump model and set-point curve. These formulations allow us to discuss how the characteristic of a pump and the set-point curve of the network influence the optimal number of FSPs and VSPs in energy terms. In general, the objective of this work is to determine the most suitable total number of pumps in a pumping station design and to determine the optimal pumping configuration in every flow rate, thus the consumed energy would be the minimum. Additionally, this methodology develops an expression to estimate the performance of a frequency inverter when a VSP operates at different rotational speeds. This work will be applied to different study cases, and the obtained results allow us to question several usual procedures for pumping control system. In general, it can be concluded that the number of pumps of a pumping system cannot be inferred in a simple form without a deep analysis of a control system. [ABSTRACT FROM AUTHOR]