Water Distribution Model Research Articles

МОДЕЛИРОВАНИЕ РЕЖИМОВ РАСПРЕДЕЛЕНИЯ ВОДНЫХ РЕСУРСОВ МЕЛИОРАТИВНЫХ СИСТЕМ ДВОЙНОГО РЕГУЛИРОВАНИЯ

The purpose of the research was to develop an algorithm for modeling water supply modes in the control loop "System section" in areas of reclamation systems of dual regulation for further development of software or information tools. The object of research was the pro-cess of water distribution on reclamation systems of dual regulation of the water regime. The information core of the work consisted of provisions on the rules of water distribution on rec-lamation systems and information technologies for automated systems, methods of processing and systematization of information. For modeling, a technique is applied with the allocation of control circuits for which standard modeling tools and algorithms are used. In the course of the research, a simulated water distribution control scheme was compiled on the reclamation systems of dual regulation with a regulating capacity in the control loop «System Section». Modeling functions are defined, such as calculation of water supply modes, modeling of wa-ter intake, transportation and supply modes, calculation of values of regulated levels and their modeling, as well as modeling of water discharge. Based on this and the determination of the initial information for modeling, an algorithm for modeling the distribution of water resources on the reclamation systems of dual regulation site was developed. The task of modeling in this "System section" circuit is to establish the modes of water supply from a regulating tank or a water source receiver by several groups of regulation «A group of water consumers». The de-veloped algorithm includes three stages: preparation for modeling, the modeling of water dis-tribution itself and the maintenance of the results of modeling results

Discussion of “Water distribution characteristics of capillary absorption in internally cured concrete with superabsorbent polymers”

In March 2024 Construction and Building Materials published “Water distribution characteristics of capillary absorption in internally cured concrete with superabsorbent polymers”, which claims to present a water distribution model characterising the spatiotemporal moisture content evolution in internally cured concrete with superabsorbent polymers during capillary absorption. This discussion, considered a post-publication critique, establishes that the paper’s water distribution model conflicts with the paper’s capillary absorption tests. While the model is based on the premise of the square-root-of-time behaviour of capillary absorption, the tests do not demonstrate that square-root-of-time behaviour. This critique in addition questions the paper’s forthright application of the power-law diffusivity expression with exponent 4, given that its validity for the paper’s materials has not been verified. It is shown that different but equivalent diffusivity expressions lead to different moisture diffusivities at lower moisture contents.

Defining Regional Water Distribution System Models

Key TakeawaysWhat defines a regional water distribution system? An AWWA committee sorted through the characteristics of systems and their respective models to come up with a clear classification.Regional water distribution models are broken into two categories: regional transmission and regional emergency supply, with many models landing somewhere along the spectrum.A close examination of four regional water systems revealed the unique attributes and numerous considerations that make developing and maintaining hydraulic models complex.

Modeling of Soil Water Distribution in a Small Mid-Latitude Watershed on the British Isle for Short Term Landslide and Flood Risk Assessment

The R-TopModel hydrological model coupled with two landslide and flood probability distribution models was applied to simulate the daily hydrological conditions of a small catchment in the Midlands of the British Isles, throughout 2017. Originally, the methodology was applied to a risk area in the tropical region. In this work, the application was extended to mid-latitude watersheds. The hydrographic basin around the Carsington Water dam (located in the Midlands of the Great Britain) is chosen because it presents risks. The model Nash-Sutcliffe Efficiency for the upstream discharge from the Carsington Water dam reached 50% with a correlation coefficient of the order of 70%, an acceptable value considering the seasonal effects of the dam on evapotranspiration and higher soil permeability. Modeling the distribution of soil moisture and excess surface water allowed obtaining the spatial distribution of the maximum conditional probability of landslides and floods in the Carsington Water catchment. These probability maps obtained are consistent with long-term susceptibility maps for Great Britain.

Designing and Solving two Mathematical Models for the Optimal Distribution of Urban Water Resources

The lack of optimal distribution of water resources in cities with a lack of quality water resources can be a threat to the sustainability of these cities.
 The present study seeks to design a method for urban water distribution among urban districts using two optimization mathematical models applied in Qom Responding to the water needs of the consumption districts was to be carried out with the least distribution costs, towards which end the first mathematical model was designed. Thus, by solving the first model, it will be clear how much water is needed to be transferred from each surface and ground resources that, while considering resources’ limitation of allocation to consumption districts, the needs of the districts are satisfied and the costs of the water company kept at the minimum.
 The scarcity of high-quality water resources in Qom has rendered water allocation from these resources to all consumption districts in the city impossible. On the other hand, urban consumption districts demand the highest-quality water given their predominant fabric (residential, commercial, or industrial). Thus, distribution management must take measures to allocate high-quality water to each district depending on its fabric, to which end the second mathematical model has been designed. Hence, solving the second model would answer the question of whether, by using the mathematical model of water distribution from various resources with different qualities, it would be possible to satisfy citizens’ needs in terms of water quality (so that the quality of the allocated water is higher than the quality demanded by the district) and ensure that optimized resource allocation would take place at minimum costs for the company.

High pH and chloramine suppress nontuberculous mycobacterial growth in a model water distribution system

This study reports the importance of maintaining a high pH and/or chloramine concentrations in water distribution system to supress the growth of nontuberculous mycobacteria (NTM) - a group containing some opportunistic pathogens. Four sets of reactor systems, each containing three reactors connected in series, were operated at three different feed water pH values (7.6, 8.4, and 9.0) and two different chloramine concentrations (2.6 and 3.8 mg/L). Altogether, 44 operational taxonomic units of NTM were identified. The NTM species Mycobacterium chelonae, M. europaeum, M. gordonae, M. stephanolepidis, M. llatzerense, M. lentiflavum, and M. kyorinense were detected in the majority of the samples. Among them, M. chelonae was highly dominant NTM species in majority of the tested samples. The NTM populations were in the range of 8.83E+ 01–6.30E+ 05 gene copies/mL. Higher relative abundances of NTM were noted in reactors containing higher chloramine residuals, but the number of NTM and total bacterial population increased with the decreasing chloramine concentration, under low pH (<8.4) and under nitrifying conditions. This study underscores the benefits of maintaining high pH in the feed as it not only increases the chloramine stability, but also suppresses the bacterial growth including NTM.

Investigating the Electro-Osmotic Coefficients of PFSA and Anion-Exchange Ionomers Using Microelectrodes

The electro-osmotic coefficient of ionomer membranes is a significant water management property that quantifies the number of water molecules dragged with the mobile ion (typically a proton) when that ion moves due to the operation of an electrochemical cell or an electric field. This coefficient becomes critical when attempting to model water distribution and movement in fuel cells and electrolyzers, where water is an important factor influencing device performance. However, there is disagreement on the value of the electro-osmotic coefficient for PFSA membranes and little significant study of the coefficient in anion exchange membranes (AEMs). Here we present an electrochemical, two-electrode method of determining the electro-osmotic coefficient of ionomers using differential relative humidity (RH) measurements. This approach allows for more accurate determination of the electro-osmotic coefficient. We present the electro-osmotic coefficient as a function of temperature and mobile ion for a variety of ionomers, including Nafion, sulfonated polystyrene, Versogen,, and Sustainion. In addition, a model based on the Maxwell-Stefan-Onsager framework is developed for the AEMs, enabling calculation of the membrane water permeability via fitting of the electro-osmotic coefficient. These coefficients will allow for more accurate models of water transport in electrochemical systems, leading to a greater understanding of the inefficiencies in these systems and, hopefully, insight into how to improve them. This work was supported by the HydroGEN Advanced Water Splitting Materials consortium, which is supported by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under contract number DE-AC02-05CH11231.

A Comprehensive Survey of Machine Learning Methodologies with Emphasis in Water Resources Management

This paper offers a comprehensive overview of machine learning (ML) methodologies and algorithms, highlighting their practical applications in the critical domain of water resource management. Environmental issues, such as climate change and ecosystem destruction, pose significant threats to humanity and the planet. Addressing these challenges necessitates sustainable resource management and increased efficiency. Artificial intelligence (AI) and ML technologies present promising solutions in this regard. By harnessing AI and ML, we can collect and analyze vast amounts of data from diverse sources, such as remote sensing, smart sensors, and social media. This enables real-time monitoring and decision making in water resource management. AI applications, including irrigation optimization, water quality monitoring, flood forecasting, and water demand forecasting, enhance agricultural practices, water distribution models, and decision making in desalination plants. Furthermore, AI facilitates data integration, supports decision-making processes, and enhances overall water management sustainability. However, the wider adoption of AI in water resource management faces challenges, such as data heterogeneity, stakeholder education, and high costs. To provide an overview of ML applications in water resource management, this research focuses on core fundamentals, major applications (prediction, clustering, and reinforcement learning), and ongoing issues to offer new insights. More specifically, after the in-depth illustration of the ML algorithmic taxonomy, we provide a comparative mapping of all ML methodologies to specific water management tasks. At the same time, we include a tabulation of such research works along with some concrete, yet compact, descriptions of their objectives at hand. By leveraging ML tools, we can develop sustainable water resource management plans and address the world’s water supply concerns effectively.

Equity analysis of intermittent water supply systems by means of EPA-SWMM

Abstract Intermittent water supply (IWS) is a frequent operation approach in developing countries. A number of factors contribute to IWS, such as leakage and water shortage, leading to inequitable water distribution. A way to reduce the inequity in IWS systems is by planning or adapting the network for equitable water distribution, which requires software capable of describing IWS conditions, including not only pressurized flow but also free-surface. In this paper, a new index for equity analysis is presented and compared with the existing indices available in scientific literature. The comparison is based on the EPA-SWMM modelling framework and standard IWS operations, including pipe emptying and filling, have been considered. Results reveal that EPA-SWMM has great potential in simulating IWS systems, especially in the application for equity analyses, as it provides a more realistic description of the pipe filling and emptying operations compared to standard water distribution modelling software. Furthermore, a novel equation called volumetric coefficient was developed which has a significant advantage in identifying the nodes with a higher impact on network equity, and ensuring the fair distribution of supply along the distribution network, considering the relevance of nodal demand, which none of the other indexes in the literature were addressed.

Effect of aggregate size on water distribution and pore fractal characteristics during hydration of cement mortar based on low-field NMR technology

The influence of aggregate size (AS) on the hydration of cement mortar is very important for improving the quality and stability of cement mortar. This study aims to study the effect of AS on water distribution and pore structure characteristics on the early-age hydration of cement mortar by low-field NMR technology. The hydration degree and fractal dimension of the hydration process were calculated by the T2 spectrum. The water distribution models at different times and locations during the hydration process were established based on the MRI bitmap data. The variation law of water volume at different locations was studied. The results indicate that: In the process of hydration, some of the water is consumed by the hydration reaction, and some of the water oozes out. The water in the large pores flows to the small pores under the action of hydrostatic pressure. AS affected the uniformity of the cement mortar at the initial state, and the gradation of the sand could improve the uniformity. The smaller AS was, the more complex the pore water distribution and changed during hydration. The bleeding mass was directly proportional to the porosity and inversely proportional to the specific surface area of particles. The effect of porosity on bleeding mass was more significant than AS. Pore fractal dimension was negatively correlated with aggregate diameter. In the initial stage, when the aggregate composition became complex, the change of fractal dimension with time also became complex. The fractal dimension increased gradually with the increase of hydration time. The gel pores (G) did not have fractal characteristics from beginning to end, capillary pores (C) and transition pores (T) had fractal characteristics after a particular time of hydration reaction. Although the air-voids (A) had fractal characteristics from beginning to end, they were not continuous.

Water distribution and scheduling model of an irrigation canal system

A complete water distribution scheme should include the scheduling of the check gates and turn out gates. This study aims to resolve the water distribution problem in irrigation districts based on channel hydrodynamic simulation and using the hydraulic factor of water level increase in backwater areas. The supply-decided water distribution and scheduling model(SD-WDSM), the demand-decided water distribution and scheduling model(dd-WDSM) were established respectively. The model was applied to the Bojili irrigation district to verify it’s applicability. The results show that the SD-WDSM can adjust the length of the backwater area through the operation of the check gate, ensuring a large flow rate at the turn out gate. The dd-WDSM was established to group the water diversion canals by rotation irrigation, and the turn out gate in the same group could open and close simultaneously, which is convenient for the administrator to operate. The two models also ensure that the water is diverted as early as possible, and the operation numbers of the check gates and the turn out gates are less. The model obtains the complete scheduling scheme of the check gates and the turn out gates in the water distribution system. This model can improve agricultural water use efficiency and promote sustainable agricultural development. The proposed model is universal and can be applied to other irrigation districts.

Decision-making for the hazard ranking of water distribution networks using the TOPSIS method

Abstract Owing to the consecutive occurrence of water quality incidents, such as the black and red water situation in Incheon, Mullae (Seoul), and Pohang, as well as the tap water larval events in Incheon and Jeju in 2020, South Korea's Ministry of Environment announced the new addition of Article 12-2 of the Enforcement Decree of the Water Supply and Waterworks Installation Act 2021. Additionally, the importance of intensive management for vulnerable areas where water quality incidents and complaints may occur repeatedly was specified. Therefore, this study suggests the hazard ranking of district-metered areas in the study area using the deterioration of the water distribution network, complaints (water quality, leakage), and modeling results (water pressure, residual chlorine concentration) to support the establishment of a reasonable water distribution network maintenance plan. The effective and sustainable maintenance of the water distribution network is possible if the hazard ranking is regularly determined using the suggested methodology proposed herein and the water distribution network intensive management area is managed.

Retracted: Modeling and Optimization of Water Distribution in Mineral Processing considering Water Cost and Recycled Water.

[This retracts the article DOI: 10.1155/2022/2314788.].

Effects of crystal chemistry on adsorption, occurrence, and mobility of water in palygorskite tunnels

Abstract Palygorskite is a fibrous magnesium-rich clay mineral with a typical tunnel structure, and its adsorption properties make it an ideal adsorbent for broad applications. Thus, revealing the confinement effects on tunnel species can help in understanding its adsorption properties. Grand canonical Monte Carlo and molecular dynamics simulations were performed to analyze the effects of the crystal chemistry of palygorskite on the adsorption, occurrence, and mobility of tunnel water. Water adsorption isotherm, distribution models, and mobility were achieved from these simulations. Zeolitic water emerges into the tunnels even at a low relative humidity (RH) (such as 5%) and completely fills the tunnels as the RH increases to 10%. In neutral palygorskite, the influence of the octahedral type on water adsorption is not obvious, but the influence of tunnel cations is obvious. The occupation of Na+ ions in tunnels can reduce the maximum water amount and affect the spatial distribution of zeolitic water. The water distribution in tunnels can be described by a two-zeolitic water-site model for neutral palygorskite and a one-zeolitic water-site model for the charged one. The zeolitic water confined in the tunnel presents very low mobility, and the appearance of Na+ ions in the charged palygorskite further reduces the mobility of zeolitic water. Compared with other clay minerals, the much lower water mobility of palygorskite implies that it may have a more efficient fixation on foreign molecules or ions in environmental applications.

A spatial agent-based model for hydraulic fracturing water distribution

Agent-based modeling (ABM) has been employed to understand and capture the complexity of the coupled human-nature processes in water resource systems. One of the challenges is to model human decisions in the coupled human and natural systems. Hydraulic fracturing water uses were distributed through a depot-based water allocation system in the Bakken region of western North Dakota, United States. In this study, a spatially explicit ABM was developed to simulate this unique water allocation system. In the ABM, institution theory was used to model the State’s regulatory policies and procedures, while evolutionary programming was employed to allow the water-depot owners (or agents) to select appropriate strategies when applying for water permits. Cognitive maps simulated the water-depot agents’ ability and willingness to compete for more water sales. All agents had their influence boundaries that restricted their competitive behavior toward their neighbors, but not for non-neighboring agents. The decision-making process was constructed and parameterized with both quantitative and qualitative information. The ABM was calibrated against real-world water-use data, and the calibration results showed that the spatial ABM performed well in simulating the total number of water depots as well as the locations and water uses of water depots at the county level. By linking institution theory, evolutionary programming, and cognitive maps, our study exhibited a new exploration of modeling the highly complex dynamics of the decision-making process involved in coupled human-nature water resource systems.

Maintaining the long-term accuracy of water distribution models with data assimilation methods: A comparative study

The upgrading of water supply services is calling for more accurate and adaptive numerical models to give insight into actual water distribution systems (WDSs), which underlines the importance of carefully calibrating model parameters. Due to unavoidable uncertainties in the calibration process such as measurement errors, errors in model parameters assumed to be known, and local-optimum of calibration algorithms, calibrated parameters could still contain non-negligible latent errors, and the calibrated model may not able to maintain its long-term accuracy when operating conditions change. To solve this problem, there is growing interest in adopting data assimilation (DA) methods to utilize more comprehensive information in long-term measurements to reduce the impact of uncertainties and maintain the accuracy and stability of calibrated models. In this study, two traditional calibration methods and four DA methods were tested and compared in two WDSs with different structures, which aims to form a general understanding of the behavior and applicability of different methods. The calibration results show that DA methods perform better than traditional methods and are more robust to different types of uncertainties, which provide an effective way to maintain the long-term accuracy of WDS models to enable better management of WDSs. Ensemble-based DA methods such as Particle Filter (PF) and Inferential-Measurement Kalman Filter (IMKF) performed well in the real-life system. They avoid linear approximation and can better estimate the impact of uncertainties to assimilate accurate correction information of the parameters. Gradient-based DA methods such as Extended Kalman Filter (EKF) and Variational Bayesian Adaptive Kalman Filter (VBAKF) have lower computational demand, but they are found to be less robust when dealing with large system uncertainties and nonlinearities.

Optimal water distribution model of canals considering the workload of managers

AbstractThe optimal operation of water distribution systems is an important research area for the modernization of irrigation schemes. In this paper, an improved 0–1 programming model is developed. This model has three objectives: minimum time of water distribution, minimum spacing of tertiary canals in a group, and the minimum difference of water distribution duration among tertiary canals in the group. The study results show that with the conventional model, 0–1 programming model and improved 0–1 programming model, the durations for the three models are 159.09, 140.50 and 141.07 h, respectively. The working distances are 44.8, 185.5 and 60.6 km. Compared with the conventional model, the lower canals of the improved 0–1 model are all large flow rate operations, while the conventional model inevitably has small flow rate operations, and the improved 0–1 model greatly reduces the duration of water distribution. Compared with the 0–1 model, the improved 0–1 model divides the adjacent canals into a group as much as possible, and the canals between groups start and end operations at the same time as much as possible, so the improved 0–1 model shortens the working distance of the staff and makes it easy for canal managers to operate canals.

Effect of Sodium Carboxymethyl Cellulose on Water and Salt Transport Characteristics of Saline-Alkali Soil in Xinjiang, China.

The scientific use of sodium carboxymethyl cellulose (CMC) to improve the production capacity of saline–alkali soil is critical to achieve green agriculture and sustainable land use. It serves as a foundation for the scientific use of CMC to clarify the water and salt transport characteristics of CMC-treated soil. In this study, a one-dimensional soil column infiltration experiment was carried out to investigate the effects of different CMC dosages (0, 0.2, 0.4, 0.6, and 0.8 g/kg) on the infiltration characteristics, infiltration model parameters, water and salt distribution, and salt leaching of saline–alkali soil in Xinjiang, China. The results showed that the final cumulative infiltration of CMC-treated soil increased by 8.63–20.72%, and the infiltration time to reach the preset wetting front depth increased by 1.02–3.96 times. The sorptivity (S) in the Philip infiltration model and comprehensive shape coefficient (α) in the algebraic infiltration model showed a trend of increasing first and then decreasing with CMC dosage, revealing a quadratic polynomial relationship. The algebraic model could accurately simulate the water content profile of CMC-treated soil. CMC enhanced the soil water holding capacity and salt leaching efficiency. The average soil water content, desalination rate, and leaching efficiency were increased by 5.18–15.54%, 21.17–57.15%, and 11.61–30.18%, respectively. The effect of water retention and salt inhibition on loamy sand was the best when the CMC dosage was 0.6 g/ kg. In conclusion, the results provide a theoretical basis for the rational application of CMC to improve saline–alkali soil in arid areas.

Evaluation of gas-rich “sweet-spot” and controlling factors of gas–water distribution in tight sandstone gas provinces: An example from the Permian He8 Member in Sulige Gas Province, central Ordos Basin, Northern China

The objective optimization of the gas-rich “sweet-spot” is the key to efficient exploration of tight sandstone gas reservoirs. However, research on evaluating the gas-rich “sweet-spot” based on the controlling factors and models of gas–water distribution of tight sandstone is limited. The sand bodies of the Permian He8 Member in Sulige Gas Province of the Ordos Basin are fluvial-delta distributary channels; the gas reservoir porosity dominantly ranges from 6% to 12%, with an average of 8.78%, and exhibits the permeability of (0.1–1) × 10–3 μm2, with a median of 0.38 × 10–3 μm2. The gas reservoirs are tight lithologic lens type with no edge and bottom water, showing a large-area quasi-continuous distribution with horizontal contiguous and vertical multi-layer superposition. Formation water related to the reservoir accumulation process is classified into paleo-formation water, paleo-condensate water, and present-condensate water. The controlling factors of gas production via the source rock and reservoir conditions exhibit distinct stages. The relationships between gas production and the source rock Ro, HGI, reservoir porosity, and permeability are positive, when gas production is <1 × 104 m3/d. However, it can be controlled by a combination of factors when gas production is >1 × 104 m3/d. Formation water production is related to a low HGI, poor physical reservoir properties, large sandstone thickness, excessive fracture development, and gaseous water condensation. Three gas–water distribution models of the gas-rich, moderate gas-rich, and complex gas–water types were established because of the accumulation conditions and gas test results in different areas. The gas-rich type (water-poor gas reservoir) is represented by the Suzhong, Sudong-I and Sudong-III areas, moderately gas-rich type (water-less gas reservoir) is distributed in the Sunan area, and gas–water complex type (water-rich gas reservoir) is mainly distributed in the Suxi-I, Suxi-II, and Sudong-II areas. Based on the analyses of the high weighted parameters of the controlling factors, the values of the gas reservoir comprehensive evaluation index (F) for commercial gas well area, low production gas well area, and gas-containing well area were >31, 26–31, and <26, respectively.

Investigating the effects of management of irrigation water distribution on farmers' gross profit under uncertainty: A new positive mathematical programming model

The Middle Eastern countries along with Iran possess an arid to semi-arid climates. For this reason, they encounter many problems in water supply and distribution within different sectors, especially agriculture. Hence, it is necessary to achieve some strategies for optimal, efficient and fair use of water supplies and irrigation grids to manage water allocation and distribution for irrigation in agricultural sector to reduce water wastes. To this end, the present study mainly aims to formulate a model for optimal water distribution for irrigation under uncertain conditions and the impact of water redistribution on the gross profit of farmers. In this study, positive mathematical programming was used and for applying uncertainty in water transfer model, robust optimization method was utilized. A combination of these two methods led to invention of a robust positive mathematical programming (RPMP) model. Tajan Irrigation and Drainage Network in northern Iran was selected as a case study to evaluate the ability of the proposed model. The results showed that with the increase in the probability of deviation (p) of the available water constraint, area under cultivation of all the selected crops decreases, and this can reduce production ultimately declining farmers' gross profits. Also, as the probability level (p) increases, amount of water transfer from upstream to downstream of irrigation and drainage network increases. Thus, cultivation structure should be mitigated for farming crops in order to prevent from reduced profit for farmers. The results of Monte Carlo Simulation indicated that using results of RPMP model were reliable and it might noticeably contribute to changing cultivation pattern.