Water Flow Research Articles

Footprint of sustained poleward warm water flow within East Antarctic submarine canyons

The intrusion of relatively warm water onto the continental shelf is widely recognized as a threat to Antarctic ice shelves and glaciers grounded below sea level, as enhanced ocean heat increases their basal melt. While the circulation of warm water has been documented on the East Antarctic continental shelf, the modes of warm water transport from the deep ocean onto the shelf are still uncertain. This makes predicting the future responses of major East Antarctic marine-grounded glaciers, such as Totten and Ninnis glaciers, particularly challenging. Here, we outline the key role of submarine canyons to convey southward flowing currents that transport warm Circumpolar Deep Water toward the East Antarctic shelf break, thus facilitating warm water intrusion on the continental shelf. Sediment drifts on the eastern flank of the canyons provide evidence for sustained southward-directed flows. These morpho-sedimentary features thus highlight areas potentially prone to enhanced ocean heat transport toward the continental shelf, with repercussions for past, present, and future glacial melting and consequent sea level rise.

Optimization of Manning's roughness coefficient using 1-dimensional hydrodynamic modelling in the perennial river system: A case of lower Narmada Basin, India.

This research bears significant implications for river management, flood forecasting, and ecosystem preservation in the Lower Narmada Basin. A more precise estimation of Manning's Roughness Coefficeint (n) will enhance the accuracy of hydraulic models and facilitate informed decision-making regarding flood risk management, water resource allocation, and environmental conservation efforts. Ultimately, this study aspires to contribute to the sustainable management of perennial river systems in India and beyond by offering a robust methodology for optimizing Manning's n tailored to the complex hydrological dynamics of the Lower Narmada Basin. Through a synthesis of empirical evidence and computational modelling, it seeks to empower stakeholders with actionable insights toward preserving and enhancing these invaluable natural resources. Using the new HEC-RAS v 6.0, a one-dimensional hydrodynamic model was developed to predict overbank discharge at different points along the basin. The study analyzes water levels, stream discharges, and river stage, optimizing Manning's n and required flood risk management. The model predicted a strong output agreement with R2, NSE, and RMSE for the 2020 eventas 0.83, 0.81, and 0.36, respectively, with an optimum Manning's n of 0.03. The lower Narmada Basin part near the coastal zone (validation point) appears inundated frequently. The paper aims to provide insights into optimizing Manning's coefficient, which can ultimately lead to better water flow predictions and more efficient water management in the region.

An Improved Water Flow Optimizer for Data Clustering

An Improved Water Flow Optimizer for Data Clustering

Dielectric size optimization for high power density in large-scale triboelectric nanogenerators

AbstractTriboelectric nanogenerators (TENGs) have emerged as a promising technology to harvest electrical energy from natural motions such as human movement, wind, and water flow. Although TENGs show significant potential in small-scale applications, developing large-scale TENGs capable of generating high power remains a significant challenge. Several factors that can affect the performance of large-scale TENGs are being investigated to overcome this challenge, including the size and configuration of dielectric materials. This study optimizes dielectrics regarding surface area, thickness, and multicell configuration to improve harvested electrical power density in large-scale TENGs. In the studies, glass fiber was used as the positive dielectric, and multipurpose white silicone was used as the negative dielectric because of their high tribo-potential, durability, and easy accessibility. In the size optimization phase, dielectric thicknesses and surface areas that provide the maximum power density were determined. Subsequently, horizontal and vertical multicell configurations were examined to efficiently integrate size-optimized dielectrics. The results reveal that large-scale TENGs with vertical multicell configurations can achieve high and usable energy density for electronics. The findings provide valuable insight into the development of large-scale TENGs with advanced power generation capabilities.

Tackling Challenges of Long-Term Electrode Stability in Electrochemical Treatment of 1,4-Dioxane in Groundwater.

Electrochemical advanced oxidation is an appealing point-of-use groundwater treatment option for removing pollutants such as 1,4-dioxane, which is difficult to remove by using conventional separation-based techniques. This study addresses a critical challenge in employing electrochemical cells in practical groundwater treatment─electrode stability over long-term operation. This study aims to simulate realistic environmental scenarios by significantly extending the experimental time scale, testing a flow-through cell in addition to a batch reactor, and employing an electrolyte with a conductivity equivalent to that of groundwater. We first constructed a robust titanium suboxide nanotube mesh electrode that is utilized as both anode and cathode. We then implemented a pulsed electrolysis strategy in which reactive oxygen species are generated during the anodic cycle, and the electrode is regenerated during the cathodic cycle. Under optimized conditions, single-pass treatment through the cell (effective area: 2 cm2) achieved a remarkable 65-70% removal efficiency for 1,4-dioxane in the synthetic groundwater for over 100 h continuous operation at a low current density of 5 mA cm-2 and a water flux of 6 L m-2 h-1. The electrochemical cell and pulse treatment scheme developed in this study presents a critical advancement toward practical groundwater treatment technology.

Study on a model analysis method of water flow characteristics in channel entrance area

With the development of inland waterway transport in our country, the demand for inland waterway navigation is increasing day by day, and the navigation safety requirements of ships are also increasing day by day. The flow condition is very important for the safe running of the ship, it not only determines the safety of the ship entering and leaving the lock, but also determines the key factor of the navigation ability of the hub. Based on the mathematical model, this paper studies the navigable flow conditions in the entrance area of the curved branching river through the modeling technology of the curved branching river, explores the peer flow characteristics of the curved branching river, and puts forward an effective measure to improve the navigable flow conditions in the entrance area of the curved river, which is of great practical significance and engineering value.

Infill Well Location Optimization Method Based on Recoverable Potential Evaluation of Remaining Oil

Infill well location optimization poses significant challenges due to its complexity and time-consuming nature. Currently, determining the scope of infill wells relies heavily on field engineers’ experience, often using single indices such as the remaining oil saturation or abundance of remaining oil reserves to evaluate the potential of remaining oil. However, this approach lacks effectiveness in guiding the precise tapping of remaining oil in ultra-high water cut reservoirs. To address this, our study comprehensively considers the factors influencing the recoverable potential of remaining oil in such reservoirs. We characterize the differences in reservoir heterogeneity, scale of recoverable remaining oil reserves, water flooding conditions, and oil–water flow capacity to construct a quantitative evaluation index system for the recoverable potential of remaining oil. Recognizing the varying degrees of influence of different indices on the recoverable potential of remaining oil, we determine the objective weight of each evaluation index by combining an accelerated genetic algorithm with the projection pursuit model. This approach enables the construction of a recoverable potential index for remaining oil and forms a quantitative evaluation method for the recoverable potential of remaining oil in ultra-high water cut reservoirs. Subsequently, we establish a mathematical model for infill well location optimization, integrating and optimizing the infill well location coordinates, well length, well inclination angle, and azimuth angle. Using the main layer sand body of an oilfield in Bohai as a case study, we conducted evaluations of the remaining oil potential and infill well location optimization. Our results demonstrate that the assessment of the remaining oil potential comprehensively characterizes the influence of the reservoir’s physical properties and oil–water diversion capacity on the remaining oil potential across different regional positions. This evaluation can effectively guide the determination of infill well location ranges based on the evaluation results. Furthermore, infill well location optimization can effectively enhance reservoir development outcomes.

Freeze-thaw stability of high-internal-phase emulsion stabilized by chickpea protein microgel particles and its application in surimi.

Future applications of high-internal-phase emulsions (HIPEs) are highly regarded, but poor freeze-thaw stability limits their utilization in frozen products. This study aimed to characterize the structure of chickpea protein microgel particles (HCPI) induced by NaCl and to assess its impact on the freeze-thaw stability of HIPEs. The results showed that NaCl induction (0-400 mmol L-1) increased the surface hydrophobicity (175.9-278.9) and interfacial adsorbed protein content (84.9%-91.3%) of HCPI. HIPEs prepared with HCPI induced by high concentration of NaCl exhibited superior flocculation index and centrifugal stability, and their freeze-thaw stability was better than that of natural chickpea protein. The increase in NaCl concentration reduced the droplet aggregation and coalescence index of the freeze-thaw emulsions, diminishing the precipitation of oil from the emulsion. Linear and nonlinear rheology showed that the strengthened gel structure (higher G' values) restricted water flow and counteracted the damage to the interfacial film by ice crystals at 100-400 mmol L-1 NaCl, thus improving the viscoelasticity of the freeze-thaw emulsions. Finally, the thawing loss of surimi gel with HCPI-200 HIPE was reduced by 2.04% compared to directly adding oil. This study provided a promising strategy to improve the freeze-thaw stability of HIPEs and reduce the thawing loss of frozen products. © 2024 Society of Chemical Industry.

Hydroelectric Plant Safety: Real-Time Monitoring Utilizing Fiber-Optic Sensors.

In the context of hydroelectric plants, this article emphasizes the imperative of robust monitoring strategies. The utilization of fiber-optic sensors (FOSs) emerges as a promising approach due to their efficient optical transmission, minimal signal attenuation, and resistance to electromagnetic interference. These optical sensors have demonstrated success in diverse structures, including bridges and nuclear plants, especially in challenging environments. This article culminates with the depiction of the development of an array of sensors featuring Fiber Bragg Gratings (FBGs). This array is designed to measure deformation and temperature in protective grids surrounding the turbines at the Santo Antônio Hydroelectric Plant. Implemented in a real-world scenario, the device identifies deformation peaks, indicative of water flow obstructions, thereby contributing significantly to the safety and operational efficiency of the plant.

Assessing catchment-scale groundwater discharge: Optimal tracers and factors analysis

Identifying streamwater-groundwater interactions (SGI) is crucial for effective water resource management, especially in arid and semi-arid regions. Despite the effectiveness of tracers in detecting these interactions, their large-scale application is challenged by the variability in tracer characteristics and natural conditions. This study addresses these challenges through extensive research across seven watersheds (7636−60,916 km2) in China's Loess Plateau (CLP). We utilized multiple physicochemical and stable isotope tracers (δ2H and δ18O) to elucidate the spatiotemporal variations and controlling factors of SGI, and to estimate uncertainties in quantifying SGI using various indicators during unidirectional water exchange periods. Our findings indicated that groundwater discharge into streamwater dominates SGI in the CLP, with mean discharge ratios (the percentage of river flow that originates from groundwater discharge) varying from 10% to 57%. Significant spatial variability was observed both across and within watersheds. The central watersheds exhibited lower discharge ratios (23 ± 11%) compared to the northern (29 ± 12%) and southern (25 ± 13%) watersheds. The upper reaches showed higher discharge ratios (28 ± 12%) compared to the middle and lower reaches (22 ± 8%). Loess thickness and vegetation primarily limit groundwater discharge by affecting groundwater storage and water flow velocity. The utilization of individual isotopic or hydrochemical indicators introduces large uncertainties in quantifying groundwater discharge ratios due to isotope fractionation or water-rock interaction, while the combination of these two indicators can reduce uncertainties in quantifying SGI. This study provides valuable insights for selecting environmental tracers to quantify SGI, contributing to sustainable water resource management in arid and semi-arid regions.

On the influence of rock glacier dynamics on the runoff in basin of the Ulken Almaty (Bolshaya Almatinka) River, Northern Tien Shan

The purpose of the work was to study the dynamics of mountain stone glaciers and streams flowing down from them for an understanding their hydrological significance. Two glaciers: Morenny and Gorodetsky, were analyzed, both located in the river Ulken Almaty (Big Almatinka) basin, Northern Tien Shan. On the average, the rate of surface displacement of the Morennoye glacier is higher than that of the Gorodetsky, which is associated with increased ice content of the last one. The increase in rates of surface displacement of both stone glaciers revealed in 2021–2022 when compared to previous years turned out to be consistent with the widely discussed idea of intensification of such glaciers dynamics under the present-day climate changes and glacier retreats. It was found that the stone glaciers have a pronounced influence on the water regime, temperature and chemical composition of watercourses formed by water running out from them. They are distinguished by the almost complete absence of intraday fluctuations in the level, temperature, and specific electrical conductivity of water, which are more pronounced in rivers and streams with glacial alimentation during the summer time. Some waterflows from the Gorodetsky glacier do not freeze in winter, which is indicative of significant groundwater reserves in its body. The waters of each of the above stone glaciers differ in their characteristic mineralization, temperature, and the ratio of the major ions. The stable water flow from such glaciers can play an important role in maintaining a river runoff during periods of the low stream discharge.

Overview of microbial communities in the surface water of the Seine River to understand their response to climate change and human activities

AbstractDiverse microbial communities play a crucial role in maintaining the proper functioning of river ecosystems and are considered important indicators of river water quality. Although the Seine River being heavily impacted by human activities, little is known about the microbial communities in its surface waters. In order to monitor water quality and promote sustainable use, we studied its microbial diversity using high-throughput sequencing technology, and explored their relationships with physico-chemical properties. The dominant phyla identified were Proteobacteria, Actinobacteriota, Bacteriodota, and Cyanobacteria. The presence of the Alphaproteobacteria and Gammaproteobacteria indicates that the Seine River water nutrient profile is mainly determined by the recalcitrant organic compounds present in WWTP effluents. Bacterial diversity showed significant temporal variability with a highly significant difference in bacterial composition between 2020 and 2021, probably due to variations in water flow favoring Cyanobacteria growth. Summer displayed higher microbial activity and abundance than autumn, attributed to temperature and orthophosphate content. Spatial variation in bacterial composition was observed between sites upstream and downstream of Paris, as well as before and after of the Seine Valenton-WWTP, subject to an accumulation phenomenon and impacted by wastewater treatment. Further assessment of emerging contaminants and other pollutants is required to better understand these variations. These results provide a basic understanding of the microbial community in the Seine River, serving as a reference for assessing the impact of implementing new wastewater disinfection techniques in the near future. Graphical abstract

Regional patterns and drivers of modelled water flows along environmental, functional, and stand structure gradients in Spanish forests

Abstract. The study of the water cycle in the forest at large scales, such as countries, is challenging due to the difficulty of correctly estimating forest water flows. Hydrological models can be coupled with extensive forest data sources, such as national forest inventories, to estimate the water flow of forests over large extents, but so far the studies conducted have not analysed the role of stand structure variables or the functional traits of the forest on predicted blue and green water flows in detail. In this study, we modelled the water balance of Spanish forests using stand structure and species data from forest inventories to understand the effects of climate, stand structure, and functional groups on blue water flows. We calculated blue water and green water flows and expressed them relative to received precipitation. Relative blue water flow was mainly concentrated in the wetter regions (Atlantic and alpine biomes) of Spain (around 25 %) in comparison with the Mediterranean biomes (10 %–20 %) and during the autumn–winter season. The leaf area index (LAI) of the forest stand is the most important predictor of relative blue water, exhibiting a negative effect until it reaches a plateau at higher levels (around 2.5–3). Deciduous forests showed a greater relative blue water flow than evergreen functional groups (25 %–35 % and 10 %–25 %, respectively) primarily due to leaf fall during the autumn–winter season. This study highlights how green water is decoupled from blue water; namely, blue water depends on winter and autumn precipitation, while green water depends on the spring and summer water demand and how the species' functional traits (deciduous vs. evergreen) can influence blue water production.

Electricity generated by upstream proton diffusion in two-dimensional nanochannels.

The movement of ions along the pressure-driven water flow in narrow channels, known as downstream ionic transport, has been observed since 1859 to induce a streaming potential and has enabled the creation of various hydrovoltaic devices. In contrast, here we demonstrate that proton movement opposing the water flow in two-dimensional nanochannels of MXene/poly(vinyl alcohol) films, termed upstream proton diffusion, can also generate electricity. The infiltrated water into the channel causes the dissociation of protons from functional groups on the channel surface, resulting in a high proton concentration inside the channel that drives the upstream proton diffusion. Combined with the particularly sluggish water diffusion in the channels, a small water droplet of 5 µl can generate a voltage of ~400 mV for over 330 min. Benefiting from the ultrathin and flexible nature of the film, a wearable device is built for collecting energy from human skin sweat.

All-Organic Piezo-Photocatalytic Film with Highly Efficient Catalysis, Weak-Force Excitation, and Recyclability.

Polyaniline (PANI), a typical organic photocatalyst, has an adjustable structure and good stability, can be easily synthesized on a large scale, and is economical. PANI is doped with ions to regulate its internal structure and improve its photocatalytic performance. However, its photocatalytic performance is limited by the doping concentration and its intrinsic properties, hindering its further application. Herein, PANI films with a piezo-photocatalytic function are fabricated to improve photocatalytic performance and explore their self-powered environmental purification property. PANI/poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) sandwich films, with PVDF-HFP as the interlayer, are prepared by introducing a piezoelectric field into PANI photocatalysts, thereby achieving excellent piezo-photocatalytic performance. The as-fabricated piezo-photocatalyst degrades methyl orange at a rate of 91.2% after 60min under magnetic stirring. Owing to the low Young's modulus of the all-organic catalyst, self-powered purification is realized using the PANI/PVDF-HFP film. Leaf surfaces are functionalized by loading the film in them for removing pollutants under sunlight and water flow. Thus, this study proposes a common strategy, wherein a piezoelectric interlayer is introduced to load the organic photocatalyst for preparing an all-organic piezo-photocatalyst. This piezo-photocatalyst can be easily recycled and responds to weak forces, realizing its application for self-powered environmental purification.

Gross Error Detection and Data Correction in IIoT-Based Data Center Cooling System

A data center always require a proper cooling system. This research study a data center with water based cooling system that consists of two chillers and two in-rack coolers. To control the system, an Industrial Internet of Things (IIoT) infrastructures has been deployed. It able to monitors real-time data from various sensors such as temperature (T), pressure (P), water flow (Q). The data were supposed to be used for optimization. However, early assessment showed that there were discrepancies between the sensors. Therefore, data reconciliation method is essential to get the valid data from the sensors. This paper discusses the implementation of gross error detection and correction by using least square method and bias compensation.

Variability of the surface boundary layer of reef-building coral species

AbstractThe coral-seawater interface is an important, highly dynamic microenvironment for reef-building corals. Also known as the concentration boundary layer (CBL), it is a thin layer of seawater bordering the coral surface that dictates the biochemical exchange between the coral colony and bulk seawater. The CBL is thus a key feature that modulates coral metabolism. However, CBL variation among small-polyped coral species remains largely unknown. Therefore, we recorded over 100 profiles of dissolved O2 concentration using microsensors to characterize CBL traits (thickness, surface O2 concentration, and flux) of three small-polyped branching coral species, Acropora cytherea, Pocillopora verrucosa, and Porites cylindrica. Measurements were conducted during light and darkness combined with low or moderate water flow (2 and 6 cm s−1). We found that CBL traits differed among species. CBL thickness was lowest in A. cytherea, while P. verrucosa showed the largest depletion of surface O2 in dark and highest dark flux. In addition, we found that O2 concentration gradients in the CBL occurred with three main profile shapes: diffusive, S-shaped, and complex. While diffusive profiles were the most common profile type, S-shaped and complex profiles were more frequent in P. verrucosa and P. cylindrica, respectively, and prevailed under low flow. Furthermore, profile types differed in CBL thickness and flux. Finally, low flow thickened CBLs, enhanced changes in surface O2 concentration, and reduced flux, compared to moderate flow. Overall, our findings reveal CBL variability among small-polyped branching corals and help understand CBL dynamics in response to changes in light and water flow conditions.

Effect of vegetation cover and soil moisture on water repellency persistence of drained peat soils

AbstractPeatlands play an essential role in the environment and their conservation requires knowledge of water-related processes. Their hydrophobicity is an important factor influencing the flow of water in soils. Drainage of fens and adapting them for agricultural production have contributed to the degradation of peat soils. The main goal of this study was to evaluate the effect of vegetation cover (meadows, alder swamp and birch forest) of drained peat soils on the persistence of their water repellency as a function of their moisture content. Soil samples (Rheic Fibric Histosol and Rheic Murshic Hemic Histosol) were collected from four sites in the Biebrza Wetlands (Poland). The sites include extensive meadows, intensive meadows, alder swamp forest, and secondary birch forest. The study used the Water Drop Penetration Time (WDPT) to assess the persistence of soil water repellency during the drying of soil samples in laboratory conditions. The study proposed a three-straight lines model to describe the relationship between WDPT and soil moisture content. Results revealed that the peat soils in intensive meadows showed the highest WDPT, followed by the secondary birch and alder swamp forest. and then by semi-natural meadows, which has the lowest WDPT.

Mechanical Enhancement and Water Treatment Efficiency of Nanocomposite PES Membranes: A Study on Akçay Dam Water Filtration Application.

Polymeric membranes are widely used in water treatment because of their ease of fabrication and low cost. The flux and purification performance of membranes can be significantly improved by incorporating appropriate amounts of nanomaterials into the polymeric membrane matrices. In this study, neat poly(ether sulfone) (PES), PES/nano copper oxide (CuO), and PES/nano zinc oxide (ZnO) membranes are fabricated via phase inversion. The pure water flux of the neat PES membrane, which is 355.14 L/m2·h, is increased significantly with the addition of nano-CuO and nano-ZnO, and the pure water fluxes of the nanocomposite membranes vary in the range of 392.65-429.74 L/m2·h. Moreover, nano CuO and nano ZnO-doped PES nanocomposite membranes exhibit higher conductivity, color, total organic carbon, boron, iron, selenium, barium, and total chromium removal efficiencies than neat PES membranes. The membrane surfaces examined by Scanning Electron Microscopy (SEM) after water filtration revealed that those containing 0.5% wt. nano CuO and nano ZnO are more resistant to fouling than the membrane surfaces containing 1% wt. nano CuO and nano ZnO. Based on the results of this study, 0.5% wt. nano ZnO-doped PES membrane is found to be the most suitable membrane for use in water treatment due to its high pure water flux (427.14 L/m2·h), high pollutant removal efficiency, and high fouling resistance. When the mechanical properties of the membranes are examined, the addition of CuO and ZnO nanoparticles increases the membrane stiffness and modulus of elasticity. The addition of 0.5% and 1% for CuO leads to an increase in the modulus of elasticity by 57.95% and 324.43%, respectively, while the addition of 0.5% and 1% for ZnO leads to an increase in the modulus of elasticity by 480.68% and 1802.43%, respectively. At the same time, the tensile strength of the membranes also increases with the addition of nanomaterials.

Preparation of superhydrophobic carbon fiber composite surface with excellent dsurability

AbstractSuper‐hydrophobic surface has excellent waterproof, self‐cleaning and delayed icing properties, and is widely used in various fields, but its lack of durability restricts its large‐scale use. In this paper, carbon fiber composite material with excellent mechanical properties is selected as the substrate, PTFE nanoparticles with excellent hydrophobicity are used as the surface energy substance, and metal screen is selected as the template, combined with hot pressing molding process, a super‐hydrophobic surface with multi‐level micro‐nano structure is successfully constructed. The test shows that the water contact angle of the surface is 169°, and the rolling angle is about 2°. The contact angle of the surface is also over 150° for other liquids, and it bounces off the external water droplets for three times, so it can easily take away pollutants and keep the surface dry and clean under the action of water flow. In the same icing environment, compared with the original surface, it can prolong the freezing time of droplets by 5 times. After repeated rubbing, the surface still has superhydrophobic properties until the whole surface is completely destroyed. The preparation method used in this study is simple, and the prepared superhydrophobic surface has excellent performance, which is expected to promote the application of superhydrophobic surface in practical working conditions.Highlights The preparation method is fast, efficient, low‐energy and environment‐friendly, and the used materials are simple and economical, and can be reused. The prepared surface has excellent hydrophobic performance for different media. The prepared superhydrophobic surface has low adhesion and droplet rebound performance. The prepared superhydrophobic surface has excellent delayed icing performance. The prepared superhydrophobic surface has excellent wear resistance.