Enhanced water demand analysis via symbolic approximation within an epidemiology-based forecasting framework

Epidemiology-based models have shown to have successful adaptations to deal with challenges coming from various areas of Engineering, such as those related to energy use or asset management. This paper deals with urban water demand, and data analysis is based on an Epidemiology tool-set herein developed. This combination represents a novel framework in urban hydraulics. Specifically, various reduction tools for time series analyses based on a symbolic approximate (SAX) coding technique able to deal with simple versions of data sets are presented. Then, a neural-network-based model that uses SAX-based knowledge-generation from various time series is shown to improve forecasting abilities. This knowledge is produced by identifying water distribution district metered areas of high similarity to a given target area and sharing demand patterns with the latter. The proposal has been tested with databases from a Brazilian water utility, providing key knowledge for improving water management and hydraulic operation of the distribution system. This novel analysis framework shows several benefits in terms of accuracy and performance of neural network models for water demand112sem informaçãosem informaçã

The crucial importance of air valve characterization to the transient response of pipeline systems

[EN] Air valves are often crucial components in an air management strategy for pressurized water conveyance systems. However, the reliability of characteristic curves of air valves found in product catalogs is quite variable. This paper evaluates the consistency of a selection of product curves to basic air flow principles. Several recurring issues are identified: catalogs that present identical curves for admission and expulsion (they are, in fact, quite distinct); admission curves that are inconsistent with the isentropic inflow model; inflow (admission) curves actually consistent with the shape of the isentropic outflow model; limited validity curves that encompass only part of the subsonic flow regimen; and unclear or unstated specifications regarding the conditions under which the characterization tests were performed or their results displayed. To examine the significance of these representational issues related to air valve capacity on system behaviour, this paper uses a case study involving the simulated transient response arising from a pump trip at the upstream end of a rising water line having a distinct high point fitted with an air valve. It is found that employing inaccurate air valve characteristics in a transient simulation may potentially result in appreciable or even dangerous simulation errors.This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil (CAPES)-Finance Code 001.Tasca, E.; Karney, B.; Fuertes-Miquel, VS.; Dalfré Filho, JG.; Luvizotto Jr., E. (2022). The crucial importance of air valve characterization to the transient response of pipeline systems. Water. 14(17):1-13. https://doi.org/10.3390/w14172590113141

Aplicação de modelo de simulação-otimização na gestão de perda de água em sistemas de abastecimento Leakage management with computational model in water supply system

Este artigo apresenta a aplicação de modelo matemático-computacional de simulação e otimização para localização de fugas. O modelo proposto é fundamentado no acoplamento de um simulador hidráulico baseado no Time Marching Approach - TMA com o algoritmo otimizador de Nelder-Mead e foi aplicado em uma rede de distribuição de água da cidade de Jundiaí-SP. Nos testes realizados ficou claro o funcionamento adequado do modelo apresentado, pois a fuga simulada foi localizada, sendo observado, entretanto, a necessidade de um aprimoramento na localização dos pontos de monitoramento durante a execução da simulação.<br>This work presents a computational model as a new tool for leak localization. The considered model was developed through the coupling of hydraulic simulator based in Time Marching Approach - TMA method with the Nelder-Mead optimization algorithm. The model was applied to a real water distribution network, in the city of Jundiaí, Brazil. In the carried through tests it was clearly the adequate functioning of the presented model, therefore the simulated escape was located, being observed, however, the necessity of an improvement in the localization of the monitor points, during the execution of the simulation

Complete Operational Simulation Of Pumped Storage Schemes

Modern Pumped Storage Schemes (PSS) has been designed to operate in a variety of operational modes. In such installations, computer simulations become extremely necessary for the analysis of the whole hydraulic system. The hydraulic analysis of steady and unsteady flows are based on the Method of Characteristics (MOC) with the hydraulic structure machine data represented by Fourier Series in a Suter plane. The algorithm used in establishing the computer program as a powerful tool in simulating PSS operation is presented.32403241

A multi-objective and multi-criteria approach for district metered area design: water operation and quality analysis

Brentan, B.; Carpitella, S.; Izquierdo Sebastián, J.; Luvizotto Jr., E.; Meirelles, G. (2019). A multi-objective and multi-criteria approach for district metered area design: water operation and quality analysis. R. Company, J. C. Cortés, L. Jódar and E. López-Navarro. 110-117. http://hdl.handle.net/10251/180063S11011

A multi-objective and multi-criteria approach for district metered area design: water operation and quality analysis

Brentan, B.; Carpitella, S.; Izquierdo Sebastián, J.; Luvizotto Jr., E.; Meirelles, G. (2019). A multi-objective and multi-criteria approach for district metered area design: water operation and quality analysis. R. Company, J. C. Cortés, L. Jódar and E. López-Navarro. 110-117. http://hdl.handle.net/10251/180063S11011

District metered area design through multi-criteria and multi-objective optimization

[EN] The design of district metered areas (DMA) in potable water supply systems is of paramount importance for water utilities to properly manage their systems. Concomitant to their main objective, namely, to deliver quality water to consumers, the benefits include leakage reduction and prompt reaction in cases of natural or malicious contamination events. Given the structure of a water distribution network (WDN), graph theory is the basis for DMA design, and clustering algorithms can be applied to perform the partitioning. However, such sectorization entails a number of network modifications (installing cut-off valves and metering and control devices) involving costs and operation changes, which have to be carefully studied and optimized. Given the complexity of WDNs, optimization is usually performed using metaheuristic algorithms. In turn, optimization may be single or multiple-objective. In this last case, a large number of solutions, frequently integrating the Pareto front, may be produced. The decision maker has eventually to choose one among them, what may be tough task. Multicriteria decision methods may be applied to support this last step of the decision-making process. In this paper, DMA design is addressed by (i) proposing a modified k-means algorithm for partitioning, (ii) using a multiobjective particle swarm optimization to suitably place partitioning devices, (iii) using fuzzy analytic hierarchy process (FAHP) to weight the four objective functions considered, and (iv) using technique for order of preference by similarity to ideal solution (TOPSIS) to rank the Pareto solutions to support the decision. This joint approach is applied in a case of a well-known WDN of the literature, and the results are discussedBrentan, BM.; Carpitella, S.; Izquierdo Sebastián, J.; Luvizotto, EJ.; Meirelles, G. (2022). District metered area design through multi-criteria and multi-objective optimization. Mathematical Methods in the Applied Sciences. 45(6):3254-3271. https://doi.org/10.1002/mma.70903254327145