Water science and engineering最新文献

{"title":"Three-dimensional numerical simulation of mixing patterns at open channel confluences","authors":"Ali Aghazadegan ,&nbsp;Ali Shokri","doi":"10.1016/j.wse.2024.08.001","DOIUrl":"10.1016/j.wse.2024.08.001","url":null,"abstract":"<div><div>Open channel confluences, where two streams or rivers converge, play a crucial role in hydraulic engineering and river dynamics. These confluences are characterized by complex hydrodynamics influenced by the discharge ratios of merging water bodies. This study investigated the mixing structure at open channel confluences using three-dimensional numerical modeling. A comprehensive three-dimensional numerical model was developed and validated against a dataset obtained from controlled laboratory experiments. This dataset incorporated three-dimensional time-averaged velocity measurements. The skew-induced and stress-induced equation systems were adopted as the core governing equations, providing a framework for simulating various scenarios. A total of ten different cases were analyzed. The results highlighted the effect of discharge ratios on turbulence, lateral and vertical vorticities, and the distribution of mixing, which intensified with higher magnitudes of discharge ratios. The mixing structure, driven by velocity gradients and vorticity, revealed the significant role of lateral and vertical vorticities in determining hydrodynamic behaviors and mixing distributions at confluences. Specifically, the momentum ratio of incoming flows governed the spatial evolution of mixing processes. This study revealed that the distribution of mixing served as a key indicator for identifying the formation of mid-channel scours. High normalized velocities induced toward the left bank led to the superelevation of the water surface, enhancing the potential for bed material and the formation of significant scour holes beneath the elevated water surface. This novel approach provides a deeper understanding of the mixing patterns at confluences, particularly in scenarios with equilibrated discharge ratios but in different magnitudes.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 236-246"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational and experimental analysis of flow velocity and complex vortex formation around a group of bridge piers","authors":"Nima Ikani ,&nbsp;Jaan H. Pu ,&nbsp;Prashanth Reddy Hanmaiahgari ,&nbsp;Bimlesh Kumar ,&nbsp;Ebrahim Hamid Hussein Al-Qadami ,&nbsp;Mohd Adib Mohammad Razi ,&nbsp;Shu-yan Zang","doi":"10.1016/j.wse.2025.01.003","DOIUrl":"10.1016/j.wse.2025.01.003","url":null,"abstract":"<div><div>In this study, the flow characteristics around a group of three piers arranged in tandem were investigated both numerically and experimentally. The simulation utilised the volume of fluid (VOF) model in conjunction with the <em>k</em>–<em>ɛ</em> method (i.e., for flow turbulence representations), implemented through the ANSYS FLUENT software, to model the free-surface flow. The simulation results were validated against laboratory measurements obtained using an acoustic Doppler velocimeter. The comparative analysis revealed discrepancies between the simulated and measured maximum velocities within the investigated flow field. However, the numerical results demonstrated a distinct vortex-induced flow pattern following the first pier and throughout the vicinity of the entire pier group, which aligned reasonably well with experimental data. In the heavily narrowed spaces between the piers, simulated velocity profiles were overestimated in the free-surface region and underestimated in the areas near the bed to the mid-stream when compared to measurements. These discrepancies diminished away from the regions with intense vortices, indicating that the employed model was capable of simulating relatively less disturbed flow turbulence. Furthermore, velocity results from both simulations and measurements were compared based on velocity distributions at three different depth ratios (0.15, 0.40, and 0.62) to assess vortex characteristic around the piers. This comparison revealed consistent results between experimental and simulated data. This research contributes to a deeper understanding of flow dynamics around complex interactive pier systems, which is critical for designing stable and sustainable hydraulic structures. Furthermore, the insights gained from this study provide valuable information for engineers aiming to develop effective strategies for controlling scour and minimizing destructive vortex effects, thereby guiding the design and maintenance of sustainable infrastructure.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 247-258"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of damming on nutrient transport and transformation in river systems: A review","authors":"Jia-wen Gan ,&nbsp;Xun Wang ,&nbsp;Qiu-sheng Yuan ,&nbsp;Xiao-lei Xing ,&nbsp;Sheng Liu ,&nbsp;Cheng-gong Du ,&nbsp;Yu-ran Zheng ,&nbsp;Yun-xin Liu","doi":"10.1016/j.wse.2024.11.001","DOIUrl":"10.1016/j.wse.2024.11.001","url":null,"abstract":"<div><div>Large-scale damming has emerged as a prevalent global trend, significantly impacting nutrient transport and transformation, as well as the downstream ecological environment. Nitrogen and phosphorus are fundamental elements of primary productivity in aquatic ecosystems and serve as key limiting factors in reservoir eutrophication. This review focuses on the impact of damming on the transport and transformation of nitrogen and phosphorus, regarding changes in nutrient concentrations, fluxes, and proportions. Spatial changes in nitrogen and phosphorus concentrations primarily occur at the inlet and outlet of reservoirs, while temporal changes often exhibit seasonal patterns. At a global scale, phosphorus is preferentially removed from reservoirs compared to nitrogen. The factors influencing the transport and transformation processes of nitrogen and phosphorus in reservoirs include the physicochemical properties of water bodies and human activities. Additionally, nitrogen dynamics are affected by reservoir age, storage capacity, and water storage regulation modes, whereas phosphorus dynamics are also influenced by hydrodynamic conditions. Finally, this review summarizes the impact of damming on the downstream ecological environment and outlines future research directions, providing theoretical support for the management of river–reservoir ecosystems and promoting the green and sustainable development of hydropower in the context of carbon peaking and carbon neutrality goals.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 209-220"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous assessment of effects of variations in temperature and hydraulic retention time on membrane fouling in membrane bioreactors","authors":"Horieh Akbari ,&nbsp;Hossein Hazrati ,&nbsp;Abbas Nazmkhah ,&nbsp;Hanieh Shokrkar","doi":"10.1016/j.wse.2025.03.001","DOIUrl":"10.1016/j.wse.2025.03.001","url":null,"abstract":"<div><div>Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions are critical factors influencing membrane fouling. This study aimed to investigate the simultaneous impacts of temperature and hydraulic retention time (HRT) variations on membrane fouling. Experiments were conducted at three different temperatures (18°C, 25°C, and 32°C) and HRTs (6 h, 9 h, and 15 h). The results demonstrated that increases in both temperature and HRT contributed to a reduction in membrane fouling. Additionally, a positive interaction between temperature and HRT was observed in the linear slope variation of membrane permeation, with temperature variations exerting a greater influence on membrane fouling than HRT variations. Fouling factor analysis revealed that increases in temperature and HRT led to decreased concentrations of soluble microbial products (SMP) and extracellular polymeric substances (EPS), particularly carbohydrates, in the activated sludge. Analyses of the cake layer of the membrane indicated that increasing temperature and HRT reduced EPS levels, particularly polysaccharides and proteins; altered primary protein structure; and increased the mean particle size distribution. Ultimately, these changes led to reductions in both reversible and irreversible hydraulic resistances. This study highlights the importance of optimizing operational parameters such as temperature and HRT to enhance membrane performance and treatment efficiency in MBR systems while mitigating fouling.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 200-208"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reservoir water level prediction using combined CEEMDAN-FE and RUN-SVM-RBFNN machine learning algorithms","authors":"Lan-ting Zhou ,&nbsp;Guan-lin Long ,&nbsp;Can-can Hu ,&nbsp;Kai Zhang","doi":"10.1016/j.wse.2025.01.002","DOIUrl":"10.1016/j.wse.2025.01.002","url":null,"abstract":"<div><div>Accurate prediction of water level changes in reservoirs is crucial for optimizing the operation of reservoir projects and ensuring their safety. This study proposed a method for reservoir water level prediction based on CEEMDAN-FE and RUN-SVM-RBFNN algorithms. By integrating the adaptive complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) method and fuzzy entropy (FE) with the new and highly efficient Runge–Kuta optimizer (RUN), adaptive parameter optimization for the support vector machine (SVM) and radial basis function neural network (RBFNN) algorithms was achieved. Regression prediction was conducted on the two reconstructed sequences using SVM and RBFNN according to their respective features. This approach improved the accuracy and stability of predictions. In terms of accuracy, the combined model outperformed single models, with the determination coefficient, root mean square error, and mean absolute error values of 0.997 5, 0.241 8 m, and 0.161 6 m, respectively. In terms of stability, the model predicted more consistently in training and testing periods, with stable overall prediction accuracy and a better adaptive ability to complex datasets. The case study demonstrated that the combined prediction model effectively addressed the environmental factors affecting reservoir water levels, leveraged the strength of each predictive method, compensated for their limitations, and clarified the impacts of environmental factors on reservoir water levels.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 177-186"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of scale effects in physical modeling of combined ogee and sharp-crested weir flow using a 3D CFD model","authors":"James Zulfan ,&nbsp;Bobby Minola Ginting ,&nbsp;Ravi Anthony Tartandyo","doi":"10.1016/j.wse.2024.11.002","DOIUrl":"10.1016/j.wse.2024.11.002","url":null,"abstract":"<div><div>Research on scale effects on flows over weirs has been conducted on a limited basis, primarily focusing on flows upstream of a single-type weir, such as ogee, broad-crested, and sharp-crested (linear and non-linear) weirs. However, the scale effects downstream of these single-type weirs have not been thoroughly investigated. This study examined the scale effects on flows over a combined weir system consisting of an ogee weir and a sharp-crested weir, both upstream and downstream, utilizing physical modeling at a 1:33.33 scale based on Froude similarity and three-dimensional (3D) computational fluid dynamics (CFD) modeling. The sharp-crested weir in this study was represented by two sluice gates that remain closed and submerged during flood events. The experimental data confirmed that the equivalent discharge coefficients of the combined weir system behaved similarly to those of a sharp-crested weir across various <em>H</em>/<em>P</em> (where <em>H</em> is the total head, and <em>P</em> is the weir height) values. However, scale effects on the discharge rating curve due to surface tension and viscosity could only be minimized when <em>H</em>/<em>P &gt;</em> 0.4, <em>Re</em> &gt; 26 959, and <em>We</em> &gt; 240 (where <em>Re</em> and <em>We</em> are the Reynolds and Weber numbers, respectively), provided that the water depth exceeded 0.042 m above the crest. Additionally, <em>Re</em> greater than 4 × 10⁴ was necessary to minimize scale effects caused by viscosity in flows in the spillway channel and stilling basin (with baffle blocks). The limiting criteria aligned closely with existing literature. This study offers valuable insights for practical applications in hydraulic engineering in the future.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 225-235"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Degradation of tetracycline in water using hydrogen peroxide activated by soybean residue-derived magnetic biochar","authors":"Van-Truc Nguyen ,&nbsp;Nguyen Duy Dat ,&nbsp;Thi-Giang-Huong Duong ,&nbsp;Viet-Cuong Dinh ,&nbsp;Thi-Dieu-Hien Vo","doi":"10.1016/j.wse.2024.10.001","DOIUrl":"10.1016/j.wse.2024.10.001","url":null,"abstract":"<div><div>Tetracyclines (TCs) are the second most commonly used antibiotics worldwide, utilized in medical treatments and animal husbandry. Although effective against various infectious diseases, TC residues persist in the environment and contribute to the emergence of antibiotic-resistant pathogens, posing significant risks to human health. This study employed the heterogeneous Fenton process to degrade TC using soybean residue-derived magnetic biochar (Fe-SoyB) as the catalyst. The Fe-SoyB sample was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and superconducting quantum interference device (SQUID) techniques. The effects of key parameters, including pH, H₂O₂ concentration, catalyst dosage, and initial TC concentration, on TC degradation were investigated. The results indicated that the TC removal efficiency decreased with increasing initial TC concentration, while it was improved with higher H₂O₂ concentrations and greater catalyst dosages. The optimal conditions for the Fenton-like process were determined: a pH of 3, a H₂O₂ concentration of 245 mmol/L, an initial TC concentration of 800 mg/L, and a catalyst dosage of 0.75 g/L, achieving a removal efficiency of 90.0% after 150 min. Additionally, the TC removal efficiency of the Fe-SoyB system varied significantly across different water matrices, with 87.1% for deionized water, 78.5% for tap water, and 72.5% for river water. The catalyst demonstrated notable stability, maintaining a TC removal efficiency of 79.7% after three cycles of use. Overall, Fe-SoyB shows promise as a cost-effective catalyst for the elimination of organic pollutants in aqueous solutions.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 129-140"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy flow rate equation for river networks","authors":"Sai-yu Yuan ,&nbsp;Jia-wei Lin ,&nbsp;Hong-wu Tang","doi":"10.1016/j.wse.2025.04.003","DOIUrl":"10.1016/j.wse.2025.04.003","url":null,"abstract":"<div><div>Rational allocation of water flow energy in river networks is essential to addressing water-related issues in river network areas. However, current methods of calculating the spatiotemporal distribution of flow energy in river networks lack precision and efficiency. This paper introduces a novel hydrodynamic representation, the energy flow rate, defined as the product of the flow rate and kinetic energy head, to quantify the kinetic energy stored and transported in river networks. A linear equation system for the energy flow rate in a river network has been theoretically derived, enabling rapid calculations under steady flow conditions. A simplified equation is proposed to describe the exponential decay of the energy flow rate, accompanied by potential energy conversion. The coefficients in the linear equation system are determined using control equations at flow confluence and diversion nodes. This study provides foundational insights that can be used to develop new hydrodynamic modeling strategies to regulate water flow energy and achieve coordinated management of water-related issues in river networks.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 2","pages":"Pages 221-224"},"PeriodicalIF":3.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of breach parameter models on hazard classification of off-stream reservoirs","authors":"Nathalia Silva-Cancino ,&nbsp;Fernando Salazar ,&nbsp;Ernest Bladé ,&nbsp;Marcos Sanz-Ramos","doi":"10.1016/j.wse.2024.05.001","DOIUrl":"10.1016/j.wse.2024.05.001","url":null,"abstract":"<div><div>The classification of dams or off-stream reservoirs concerning potential hazards in the event of failure often involves the use of two-dimensional hydraulic models for computing floodwave effects. These models necessitate defining breach geometry and formation time, for which various parametric models have been proposed. These models yield different values for average breach width, time of failure, and consequently, peak flows, as demonstrated by several researchers. This study analyzed the effect of selecting a breach parametric model on the hydraulic variables, potential damages, and hazard classification of structures. Three common parametric models were compared using a set of synthetic cases and a real off-stream reservoir. Results indicated significant effects of model choice. Material erodibility exerted a significant impact, surpassing that of failure mode. Other factors, such as the Manning coefficient, significantly affected the results. Utilizing an inadequate model or lacking information on dike material can lead to overly conservative or underestimated outcomes, thereby affecting hazard classification.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 1","pages":"Pages 102-114"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141047156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ciprofloxacin (CIP)-polluted water treatment via a facile mechanochemical route: Influencing factors and mechanism insights","authors":"Xiao-yi Wang ,&nbsp;Cheng-liang Dong ,&nbsp;Kun Xu ,&nbsp;Ri-long Xiao ,&nbsp;Xiu-juan Feng","doi":"10.1016/j.wse.2024.03.004","DOIUrl":"10.1016/j.wse.2024.03.004","url":null,"abstract":"<div><div>Degrading ciprofloxacin (CIP)-polluted water has recently emerged as an urgent environmental issue. This study introduced mechanochemical treatment (MCT) as an innovative and underexplored approach for the degradation of CIP in water. The influence of various additives (CaO, Fe₂O₃, SiO₂, Al, and Fe) on CIP degradation efficiency was investigated. Additionally, six types of composite additives (Fe–CaO, Fe–Fe₂O₃, Fe–SiO₂, Fe–Al, Al–SiO₂, and Al–CaO) were explored, with the composite of 20% Fe and 80% SiO₂ exhibiting notable performance. The impacts of additive content, pH value, and co-existing ions on CIP degradation efficiency were investigated. Furthermore, the effectiveness of MCT in degrading other medical pollutants (norfloxacin, ofloxacin, and enrofloxacin) was verified. The transformations and changes in the crystal structure, oxidation state, microstructure, and morphology of the Fe–SiO₂ composite additive were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. This study proposed a sigmoid trend kinetic model (the Delogu model) that better elucidates the MCT process. Three plausible degradation pathways were discussed based on intermediate substance identification and pertinent literature. This study not only establishes a pathway for the facile degradation of CIP pollutants through MCT but also contributes to advancements in wastewater treatment methodologies.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"18 1","pages":"Pages 21-29"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140271996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}