Author(s): Domagoj Nakic; Bojan Djurin; Bozo Soldo; Drazen Vouk

Linked Author(s): Domagoj Nakić

Keywords: Water tank; Optimal volume; Maximum daily consumption; Consumption pattern; Program code

Abstract: Modeling pumping and consumption behavior in water supply requires the analysis of numerous input and computational data, whose functional dependence is usually not easy to determine. The start and duration of pumping, the volume of water storage and the amount of maximum daily water demand, and the consumption pattern are not uniquely and linearly related variables. This paper analyzes these dependencies and provides a software solution (model represented by program code) that, based on the known maximum daily consumption and its pattern, determines the minimum required operating volume of the water tank with the associated regime of pumping water from the source into the water tank (start and duration of continuous pumping). Only the balance of the water storage is calculated, while fire and safety reserves in the water tank are excluded from the analyzes, as they are calculated based on separate guidelines and are not directly related to changes in consumption and pumping regime in the water tank. The focus is on simplifying existing "manual" calculations and adapting them to the needs of scientists, but also engineers involved in water supply system design and operational activities related to changes in the operation of pumping stations and water tank, to minimize capital costs (construction of a water tank) and operating costs (pumping). Therefore, the created program assumes for each hour of the day the start of pumping water into the water tank with different durations (1-24 hours), which gives a total of 576 different options and indicates the optimal solution (or solutions in the case of finding several equivalent options) the one for which the minimum required volume of operating reserves of the water tank is obtained. The functionality of the created program code is demonstrated using two hypothetical examples. The program was created using the JavaScript programming language (JS), which is one of the most popular and widely used programming languages nowadays. It accepts as input parameters the maximum daily consumption (m3/day) and the percentage values for each of the time intervals (hours) of consumption (24 hours - 24 intervals - 24 values), whose total sum must be 100%. The paper also includes instructions that provide steps for starting a JavaScript program on the Windows operating system, including downloading Node.js, opening and navigating it using a terminal (Command Prompt), and starting and using the program itself. A description of planned program upgrades is also given so that a desktop application with a user-friendly interface would be developed to allow wider practical application, particularly by engineers designing water supply systems. The next phase of program upgrade is to develop an additional water pumping system optimization capability based on known existing water tank volume and maximum daily consumption volume and pattern.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022686

Year: 2022