جستجوی مقالات مرتبط با کلیدواژه « water supply network » در نشریات گروه « مهندسی آب »

Water loss is a significant issue that leads to substantial damage to water resources, civil infrastructure, the environment, and water distribution companies. Urban water supply networks, particularly in regions with scarce water resources, face challenges related to water loss. Leakage from these networks constitutes a major portion of the overall water loss. Factors contributing to leakage include the aging of water supply systems, pipe damage due to soil stresses and urban traffic, fluctuations in water pressure, improper urban plumbing practices, and inadequate embankments. Examining factors such as pressure, pipe type, soil environment, and temperature can help identify the causes of leakage and effectively manage and mitigate its volume. Laboratory and field investigations have revealed that the leakage power, contrary to the pressure-leakage relationship, falls within the range of 0.5 to 2.79, with values exceeding 0.5 due to variations in pipe types, dimensions, and the type of cracks. Reducing the D50 (median grain size) of the soil and selecting an appropriate soil granulation around the pipes can effectively reduce the leakage flow rate. This article provides an overview of water wastage, its types, and underlying causes, followed by a discussion on the fundamentals of leakage calculation.

The water supply network is one of the most critical infrastructures of human societies, which could cause illness or death in many consumers due to its expanding nature. Water pollution is one of the ways of spreading biological pollutants among the population, which is known as bioterrorism today. Biological contamination usually occurs with the use of pathogens and biotoxins. Therefore, recognizing the vulnerable stages of the water supply network against various pollutants is of particular importance. In this research, in the first stage, a selection of five pathogens (Bacillus anthracis, Cryptosporidiosis, Francisella tularensis, Vibrio cholerae, Shigella) that are more likely to pollute water sources have been made. Thus, employing each component of the water supply system (including raw water source (dam)), Raw water storage tank, water treatment plant, treated water transmission line, treated water tanks, and distribution network (30 scenarios) were defined. In the next step, using multi-criteria group decision-making and employing three main criteria (vulnerability of each water supply stage, the amount of contaminant damage power, the amount of contaminant risk in each of the water supply stages) and their sub-criteria, the weight of each criterion was determined from the perspective of decision-makers by utilizing GFDM software. After analyzing the scenarios, the risk level of each scenario was ranked. Scenario 26 created the most risk, which consists of introducing the pathogen Bacillus anthracis into the distribution network. The entry of contamination into the distribution network due to high availability and lack of subsequent treatment steps, as well as the slight chance of preventing the contaminant from reaching consumers, can cause many diseases and deaths. Furthermore, it has a high resistance against chloride and is stable in water, so the entry of this contaminant into the distribution network can be dangerous. Considering the existing conditions, recognizing and calculating the risk of different scenarios can lead to readiness and increase the speed of action in response to possible biological attacks.

One of the oldest methods of producing electrical energy is the use of latent energy in running water, which uses a water turbine to achieve this. It is one of the most important sources of renewable energy and has attracted the attention of many researchers in recent years. In this study, laboratory evaluation of hydraulic performance of a type of water microturbine to convert excess pressure in medium pressure water supply networks into electrical energy usable for sensors or equipment such as flow meters, pressure meters, leak detectors, etc., used to manage energy consumption and intelligent water supply networks is investigated. For this purpose, in three different scenarios, the effect of parameters such as flow rate, pressure and different angles of the guide vane on the microturbine performance and pressure drop was investigated. The results showed that the highest microturbine output power (59.01 watts) and pressure drop rate (9.71 meters H2O) were obtained when the inlet discharge was 42.61 m3/hr and the opening guide vane was 20 degrees. It also has the lowest output power (0.8 watts) and pressure drop rate (4.65 meters H2O) for a flow rate of 46 m3/hr without the guide vane. The coefficient of determination (R2) for the equations of microturbine output power and pressure drop was calculated to be 0.92 and 0.99, respectively.