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This paper presents a study of the hydraulic response of an infinite unsaturated slope exposed to a perturbation of the ordinary seasonal climatic cycle. The ground flow is modelled via a simplified one-dimensional finite difference scheme by decomposing the two-dimensional slope seepage into antisymmetric and symmetric parts. The numerical scheme incorporates two distinct hysteretic and non-hysteretic soil water retention laws, whose parameters have been selected after a preliminary sensitivity analysis. Results indicate that, in the hysteretic case, the "memory" of the perturbation takes a long time to fade, and the ordinary soil saturation cycle is only restored after several years of normal weather. Instead, in the non-hysteretic case, the recovery of the ordinary saturation regime is almost immediate after the perturbation. In contrast with the markedly different predictions of degree of saturation, both hysteretic and non-hysteretic slope models predict virtually identical evolutions of negative pore water pressures, with an almost immediate restoration of the ordinary cycle after the perturbation. [ABSTRACT FROM AUTHOR]

Shallow reservoirs are ubiquitous in hydraulic engineering. Predicting the properties of the flow field in such reservoirs is instrumental to inform their design, operation, and maintenance. In previous research, oscillating jets were experimentally observed in rectangular shallow reservoirs, and we assess here the performance of a simple analytical model to predict the frequency of the dominating jet oscillation mode(s). The model couples the evaluation of the reservoir natural frequencies with the Rossiter feedback loop formula. The analytical predictions are compared against experimental observations by reanalyzing an existing data set. In many cases, the model predictions match the observations. Remaining discrepancies may result from experimental uncertainties, which could be reduced in future tailored laboratory tests, or from the dimensionless vortex celerity value used by the feedback loop model, which was not assessed experimentally. [ABSTRACT FROM AUTHOR]

An air-entraining vortex begins to form when the submergence of an intake is not adequate and less than the critical value known as critical submergence. In the present study, critical submergence for a laterally placed single rectangular intake under a uniform approach flow in an open channel was investigated experimentally. Analysis of the data collected in the present study reveals that critical submergence is significantly influenced by intake size, intake aspect ratios, approach Froude number, intake Froude number, intake Reynolds number, and Weber number. However, intake Froude number and intake aspect ratio were found to be the most sensitive parameters that affect critical submergence. An empirical relationship for critical submergence has been developed using collected data used to compute the critical submergence within an error of ±20%. The findings of this investigation is advantageous for hydraulic engineers when designing lateral rectangular intakes to prevent the formation of an air-entraining vortex. Practical Applications: Insufficient water cover over the hydraulic intakes causes an air-entraining vortex formation in the vicinity of the intake. The formation of such an air-entraining vortex results in significant hydraulic issues, structural damages, etc. Ensuring enough submergence for the intake during its operational period is necessary to evade such problems. The submergence at which the air-core tail of the surface vortex reaches the intake initiating air-entrainment is called critical submergence. Critical submergence is an important parameter for the design of intakes and is widely used as a parameter to determine an incipient state for which no air is entrained by intake vortices. This paper discusses the experimental investigation of critical submergence for single lateral rectangular intakes concerning significant geometrical parameters, such as intake aspect ratio, approach Froude number, intake Froude number, etc. The proposed empirical equations in this study are helpful to hydraulic engineers when computing critical submergence to fix the invert level of a lateral rectangular intake. [ABSTRACT FROM AUTHOR]

The river systems in the Himalayan region exhibit year-round flow due to precipitation during the rainy season and snow/glacier melt in summer. These rivers carry massive sediment loads, especially during monsoons. Hydraulic engineers face the challenge of designing infrastructure capable of managing this sediment. Breast wall spillways are recommended for their ability to handle floodwaters and sediment disposal. The hydraulics of breast wall/orifice spillways changes with the varying reservoir level. The flow is free flow for reservoir water levels below the top of the sluice, whereas for higher water levels the flow is orifice flow. Orifice spillways are designed to pass water through openings or gates, where the flow is primarily governed by the hydraulic head and the orifice size. The flatter bottom profile helps in smoothly directing the flow through the opening without causing significant turbulence or separation, especially when the gate is partially open. Hence, the crest profile is flatter as compared to the overflow crest profile to avoid flow separation and negative pressures on the crest for small gate openings. Kwar Hydro Electric Project is one such Himalayan region project planned across the Chenab River in which a breast wall spillway has been provided to serve the dual-purpose of flood and sediment disposal. The present paper describes the physical and numerical hydraulic model studies conducted for Kwar H.E. Project, Jammu and Kashmir, to evolve a breast wall spillway profile, ski jump type energy dissipator at the toe of the spillway. [ABSTRACT FROM AUTHOR]

The document discusses the theory and technology for preventing mine water disasters, emphasizing the importance of mine water disaster prevention for safe mining operations. Various studies explore advanced detection methods, disaster prevention technologies, and risk assessment approaches to enhance mine safety and promote sustainable development in the mining industry. The research findings cover topics such as detecting concealed water-conducting faults, monitoring drainage tunnel intrusions, studying landslide initiation mechanisms, analyzing hydrogeochemical characteristics of groundwater, and developing prediction models for water-conducting fracture zones. These studies provide valuable insights for addressing water hazards in coal mines and offer practical engineering applications and methodological guidance. [Extracted from the article]

The shaft hydropower plant (SHPP) is a novel hydraulic concept for low-head hydropower sites with several environmental and operational advantages over conventional layouts. However, the first two projects implementing this concept have shown comparatively high construction costs and project risks. Therefore, further optimization is required to increase economic attractiveness and enable broader market adoption. Initial model tests recommend a square-shaped shaft inlet with a three-sided approach flow for low-loss and fish-friendly inflow conditions. Yet, this design requires significant space for structural implementation and may be unsuitable for use with multiple shafts or as an extension of non-powered dams and weirs. This research paper presents the application of a computational fluid dynamics simulation setup to evaluate the hydraulic performance of various design configurations, especially alternative design layouts with a one-sided approach flow without further physical model tests. The simulation setup is calibrated against observations including head loss and velocity measurements from the physical model tests, and its satisfactory performance enables the analysis of alternative design layouts. This study aims to derive the most significant design parameters for achieving the desired hydraulic conditions at the intake. Increasing the flow depth before the intake and enlarging the inlet area have the most significant impact, while increasing the overflow of the front gate has the least significant effect. The chosen CFD application is deemed suitable for hydraulic design optimization and provides guidance on the key parameters to focus on for tailored site-specific design development. [ABSTRACT FROM AUTHOR]

The navigation waterways to the harbors of Rostock (Warnow Estuary), Germany, and Szczecin (Oder/Szczecin Lagoon), Poland, were recently deepened. Both activities required Environmental Impact Assessments. We conducted expert- and data-based ecosystem service assessments for both case studies. Additionally, we performed 3D-ecosystem model simulations. For the Oder Lagoon, the model results show that the waterway deepening increased the burial in sediments by 807 t N/a, 112 t P/a and 4661 T C/a. However, altogether, the impacts of the deepening to 12.5 m draught on the lagoon ecosystem are minor and a model application is not necessary, but the results improve the data basis for ecosystem service assessments. Our expert-based ecosystem service approach is adaptable to the needs of coastal engineering and hydraulic projects and is both easy and quick to apply and transferable. The assessment results highlight the relevance of cultural services and can complement EIAs. Our approach can especially support the early scoping stage of an EIA. It has the potential to enhance cooperation and communication with and between stakeholders, reduce conflicts, and save time. Additionally, it could improve the compilation and addressing of stakeholder concerns, potentially reducing costs associated with unnecessary studies. [ABSTRACT FROM AUTHOR]

Utilizing waste materials in road construction has become a compelling alternative owing to the availability of high-quality natural aggregates and the challenges associated with disposing of industrial waste. This study delves into the potential of class F fly ash from coal combustion, which is not self-cementing, requiring additional activators for stabilization. Activators such as lime, ground granulated blast furnace slag (GGBS), and bottom ash were incorporated in diverse proportions. The experimental analysis included tests like modified Proctor compaction, unconfined compressive strength (UCS), California bearing ratio (CBR), and repeated load triaxial tests. Results revealed that the introduction of 1–3% lime, 3–21% ground granulated blast furnace slag, and 10–30% bottom ash, combined with extended curing durations, augmented both compressive strength and California bearing ratio values. The resilient modulus of these mixtures showed an improvement of roughly 70% compared to traditional Wet Mix Macadam. Advanced microscopic studies using X-Ray diffraction (XRD), field emission scanning electron microscopy (FESEM) equipped with energy dispersive spectroscopy (EDS), and thermogravimetric analysis (TGA) identified the formation of calcium silicate hydrates and ettringite as contributing factors to the increased strength. The optimally formulated mixtures met the requirements outlined by the Indian Roads Congress, suggesting their suitability for inclusion in base, subbase courses of flexible pavements, and the dry lean concrete layer of rigid pavements. [ABSTRACT FROM AUTHOR]

This article addresses the reliability and safety of an earth dam in the case of a change in the reservoir water level. The water level must often be reduced to remove water or as a response to an emergency situation in the process of operation of a hydraulic structure. Lower water levels change seepage conditions, such as the surface of depression, values and directions of seepage gradients, seepage rates, and volumetric hydrodynamic loading. Practical hydraulic engineering shows that these changes can have a number of negative consequences. Higher seepage gradients can lead to seepage-triggered deformations in the vicinity of the upstream slope of a structure. Hydrodynamic loads, arising during drawdown, reduce the stability of an upstream slope of a dam and cause its failure. Potential consequences of a drawdown can be evaluated by solving the problem of drawdown seepage for the dam body and base. A numerical solution to this problem is based on the finite element method applied using the PLAXIS 2D software package. Results thus obtained are compared with those obtained using the finite element method in the locally variational formulation. A numerical experiment was conducted to analyze factors affecting the value of the maximum seepage gradient and stability of the earth dam slope. Recommendations were formulated to limit the drawdown parameters and to ensure the safe operation of a structure. [ABSTRACT FROM AUTHOR]

The enormous energy carried by discharged water poses a serious threat to the Piano Key Weir (PKW) and its downstream hydraulic structures. However, previous research on energy dissipation in PKWs has mainly focused downstream effects, and the research methods have been largely limited to physical model experiments. To deeply investigate the discharge capacity and hydraulic characteristics of PKW, this study established a PKW model with universally applicable geometric parameters. By combining physical model experiments and numerical simulations, the flow pattern of the PKW, the discharge at the overflow edges, and the variation in the energy dissipation were revealed for different water heads. The results showed that the discharge of the side wall constitutes the majority of the total discharge at low water heads, resulting in a relatively high overall discharge efficiency. As the water head increases, the proportion of discharge from the inlet and outlet keys increases, while the proportion from the side wall decreases. This change results in less discharge from the side wall and a consequent reduction in the overall discharge efficiency. The PKW exhibits superior energy dissipation efficiency under low water heads. However, this efficiency exhibits an inverse relationship with an increasing water head. The overall energy dissipation efficiency can reach 40% to 70%. Additionally, the collision of the water flows inside the outlet chamber and the mixing of the overflow jet play a primary role in energy dissipation. The findings of this study have significant implications for hydraulic engineering construction and PKW operational safety. [ABSTRACT FROM AUTHOR]

Accurate characterization of soil hydraulic conductivity influenced by temperature under a centrifugal environment is important for hydraulic and geotechnical engineering. Therefore, a temperature-influenced scaling law for hydraulic conductivity of soil in centrifuge modeling was deduced, and a temperature-controlled falling-head permeameter apparatus specifically designed for centrifuge modeling was also developed. Subsequently, a series of temperature-controlled falling-head tests were conducted under varying centrifugal accelerations to achieve the following objectives: (1) examine the performance of the apparatus, (2) investigate the influence of temperature and centrifugal acceleration on the hydraulic conductivity of sand and its scaling factor, and (3) validate the proposed scaling law for hydraulic conductivity. The main conclusions of the study are as follows. Firstly, the apparatus demonstrated good sealing and effectively controlled the temperature of both the soil specimen and the fluid. Secondly, the hydraulic conductivity of sand was not constant but varied over time, likely due to the presence of radial seepage in addition to vertical seepage as the test progressed. Thirdly, temperature significantly influenced the hydraulic conductivity of sand and its scaling factor under the same centrifugal acceleration. Therefore, it is essential to closely monitor the temperature of models during centrifugal tests. Finally, the measured and calculated values of the scaling factor index for the hydraulic conductivity of sand showed good agreement, verifying the proposed scaling law. [ABSTRACT FROM AUTHOR]

Sediment management is a significant part of the decision-making process that hydraulic engineers need to undertake as it has a direct bearing on the environment. Sediment dredging from around intake structures and reservoirs impose a high operating cost. Jets can efficiently remove large quantities of sediment at low operational costs. This study assesses the scouring pattern development by changing nozzle parameters to achieve maximum scouring conditions. Toward this end, scour holes induced by jets generated using the nozzles with four inner angles (30°, 45°, 60°, and 90°) are tested on a cohesionless sediment bed. The experimental results show that the inner nozzle angle, α, and the densimetric Froude number, F0, affect the scour pattern. This work illustrates that the scour hole dimensions grow with increasing α and F0. Based on the velocity measurements, for the range of jet discharges considered herein, the relative velocity Um/U0 is increased by 20%–25% for the nozzle with α = 90° compared to the nozzle with α = 30°. [ABSTRACT FROM AUTHOR]

Spur dikes are deployed to regulate the flow in an open channel for navigation and bank protection as well as protection of beaches against erosion. The spacing between spurs is a crucial design parameter. The reattachment length at the lee side of a single spur dike may be viewed as the maximum spacing between consecutive spurs, as a larger spacing may result in propagation of the recirculation flow toward the bank between them. This paper presents a physically based approach to characterize and compute the reattachment length in the lee side of a vertical spur dike under both fixed and mobile beds. A new model is introduced based on the principles of momentum and energy. The reattachment length is inversely proportional to the scour depth, resulting in approximately a 4%‒38% reduction when reaching the equilibrium scour compared to no scour condition, and the relative reattachment length ranges from 8.5 to 13.5b for the scoured bed. The model is applied to the field data, and the predicted reattachment length is compared with the spacing between two consecutive spurs. This formula performs better in estimating the reattachment length than other reported formulas. It proves useful for hydraulic engineers to decide the efficient design spacing between spurs during bank protection and navigation channel regulation design. [ABSTRACT FROM AUTHOR]

The Linpan cultural landscape has been a masterpiece of harmonious coexistence between humans and nature since the Dujiangyan Hydraulic Engineering more than 2,300 years ago. With the rapid urbanization of the Chengdu Plain over the past thirty years, Linpan has gradually declined and faced a disappearance crisis. The protection and utilization of Linpan have become an urgent public demand. Our case study area was in Dujiangyan City. We used detailed field investigations, questionnaires, and unstructured interviews to understand the villagers' perceptions of the Linpan and explore how their socioeconomic and resource backgrounds affected their landscape perceptions. The study revealed typical population loss and aging trends in Linpan settlements, and it found that the villagers recognized Linpan as a "joint masterpiece of man and nature" and that most villagers supported the utilization in Linpan rural areas. This study further revealed that villagers' socioeconomic and resource background factors had complex and selective impacts on their landscape perceptions. It also found that economic factor, especially monthly income, was the key variables affecting villagers' landscape perceptions. The study enriched the perception study of Linpan, a unique agro-cultural landscape in the Chengdu Plain. It provided an essential reference for the subsequent sustainable development of Linpan based on villagers' participation. [ABSTRACT FROM AUTHOR]

A digital twin is a new trend in the development of the current smart water conservancy industry. The main research content of intelligent water conservancy is clarified. This paper first summarizes and combs the relevant system architecture of smart water conservancy, and puts forward a smart water conservancy framework based on digital twins, highlighting the characteristics of virtual and real interaction, and symbiosis of the water conservancy twin platform. Secondly, the status quo of intelligent water conservancy "sky, air, ground and water" integrated monitoring technology, big data and artificial intelligence, model platform technology, knowledge graph and security technology is analyzed. From the perspective of application, the research progress of each technology in water security, water resources and hydraulic engineering is reviewed. Although the construction of smart water conservancy has made remarkable progress, it still faces many challenges such as data governance, technology integration and innovation, and standardization. In view of these challenges, this paper puts forward a series of countermeasures, and looks forward to the future development direction of intelligent water conservancy. [ABSTRACT FROM AUTHOR]

Safety monitoring of hydraulic structures is a critical task in the field of hydraulic engineering construction. This study developed a method for preprocessing and classifying monitoring data for the identification of gross errors in hydraulic structures. By utilizing linear regression and wavelet analysis techniques, it effectively differentiated various waveform characteristics in data sets, such as Sinusoidal Wave Cyclical, Triangular Wave Cyclical, Seasonal Cyclical, and Weakly Cyclical growth types. In the experiments for gross error identification, the 3σ algorithm, K-medoids algorithm, and Isolation Forest algorithm were applied to test the data. The results showed that the K-medoids algorithm excelled in processing Sinusoidal Wave Cyclical Data Sets; the 3σ algorithm adapted better to Triangular Wave Cyclical Data Sets; the Isolation Forest algorithm performed well in handling data sets with significant anomalies or atypical fluctuations and excelled in scenarios with strong seasonality and large data fluctuations; and for complex Weakly Cyclical Growth Data Sets, all three algorithms were less effective, indicating the potential need for more advanced analysis methods or a combination of multiple techniques. Testing on actual engineering data further confirmed the importance of using specific gross error identification techniques for special data types after data set pre-classification, providing a more effective technical solution for the safety monitoring of hydraulic structures. [ABSTRACT FROM AUTHOR]

River bank protection is vital in hydraulic river engineering to preserve natural rivers, lands, and critical constructions such as bridges. Spur dikes are erosion-protective structures that protrude outward from the river bank in different orientations to deflect the flow away from the riverbank. The present experimental study provides insight into the temporal variation in bed morphology and scours around rectangular-shaped spur dikes with different orientations, such as 60º, 90º, and 120º. Also, maximum scour depth (MSD) is developed compared to the condition when downward seepage is applied. The experiments examined the suitability of various spur dike orientation configurations and the scour development over time, specifically at intervals of 2, 12, and 24 hours, and compared with 24 hours (Seepage). Results showed that the orientation angle of 90º generated the highest scour depth, while the least scour depth was found with an orientation angle of 120º. The downward seepage intensifies the motion of sediment particles and leads to an escalated particle detachment, resulting in deeper scour depressions. The development of scour depth is initiated from the spur dike tip and reaches its maximum there. The deposition of sand particles shifted downstream, and a dune-like structure formed near the second spur dike. [ABSTRACT FROM AUTHOR]

Abstract Existing anchor solutions are limited in their applicability to the floating offshore wind industry, which demands prolonged load endurance in extreme weather conditions and varied seabed soils. This limitation restricts project feasibility and increases costs. In order to address these challenges, the Deeply Embedded Ring Anchor (DERA) is proposed to achieve substantial reductions in anchor costs through efficiency enhancements. Ensuring the long-term safety and reliability of the DERA, especially considering a minimum operational period of 25 years, necessitates a comprehensive understanding of fatigue damage. Induced by repetitive loading below material yield strength, fatigue poses a significant threat to structures exposed to waves and currents. Anchors, vital for station keeping, are susceptible to fatigue damage, particularly in the padeye area. This paper conducts a fatigue analysis, focusing on factors such as the wall thickness of the ring anchor, inner stiffeners, and stiffener thickness, to evaluate the performance of DERA in this context. The results showed that the stiffener significantly affects the elongation of the total life of the anchor. In conclusion, this paper focuses on advancing innovations like DERA, enabling the efficient utilization of offshore wind resources, and addressing safety concerns through meticulous fatigue analysis.

Abstract Surface-projected piles, such as helical and under-reamed piles, are widely utilized in geotechnical engineering to enhance the load-carrying capacities of pile structures with surface projection part. Despite the use of a wide variety of surface-projected conditions, detailed investigations considering various dimensions and angles of surface-projected piles remain limited in the current literature. This study aims to assess the effects of surface-projected widths w p (10 mm, 20 mm, 40 mm) and angles θ (18°, 27°, 45°, 90°) on pile penetration resistance using a two-dimensional model and PIV analysis. Wider projections increased resistance, with a maximum of 1.84 kN—57% higher than conventional piles in the model ground. Penetration resistance was proportional to width at 90°; for w p = 20 mm, penetration resistance decreased with increasing θ, while for w p = 40 mm, it increased. Theoretical ultimate bearing capacity calculations emphasize differences from experimental results due to neglected shaft friction. Residual penetration resistance and particle displacement were observed for w p of 20 mm and 40 mm after failure. This study provides insights into optimizing surface-projected pile design and understanding ground failure mechanisms.

Entre los meses de diciembre a abril, regiones del norte del Perú, entre ellas Lambayeque, se ven afectados por eventos extremos máximos, ocasionando estragos en viviendas, inundación de campos de cultivo, colapso de obras hidráulicas y, lo más irreparable, pérdida de vidas humanas. En esa línea, el objetivo de la presente investigación fue aplicar redes neuronales artificiales al modelamiento de lluvia-escorrentía en una cuenca del norte de Perú, en específico, en la cuenca del río Chancay Lambayeque, perteneciente a la vertiente del Pacífico. Para ello se recopilaron registros de precipitación y caudales de 30 años (normal hidrológica), de 12 estaciones hidrometeorológicas pertenecientes tanto a la cuenca como aledañas a ésta. Así, aplicando un modelo de redes de memoria a largo y corto plazo (LSTM), se procedió a modelar la lluvia, buscando seguir el comportamiento de los caudales observados en la estación hidrométrica Racarrumi; con un 80 % de la información se entrenó al modelo y con un 20 % se validó. En suma, se obtuvo que en la etapa de validación del modelamiento, el coeficiente de Nash fue de 0.93, correspondiéndole el calificativo de “muy bueno”.

The city of Arequipa, the second most important city in Perú, faces numerous daunting challenges, including high-intensity but short-in-duration rainfalls that leads to floods and the swelling of the Chili River (mud and landslides). This situation aggravates the vulnerability of the population settled on the margins of the gorges and gullies, due to little or no territorial planning from public institutions. The local news evidence negligence every year, both in terms of human lives and infrastructure loss. The frequency of these events has increased with time and that is the reason for prompting the establishment of rainfall thresholds and the compilation of a 41-year record (1981-2021), with the aim of informing about the dangerousness of an adverse meteorological phenomenon, either predicted or in progress. For the hydrological model, the authors used the highest 24-hour precipitation data from the SENAMHI's stations (National Service of Meteorology and Hydrology of Peru) to generate the liquid hydrograph for different return periods with the Hydrologic model of HEC-HMS. Soil mechanics studies were also carried out to determine the rheological parameters of the non-Newtonian flow and then calibrate through historical events in a hydraulic model of HEC-RAS. Finally, cartographic maps in QGIS were prepared to evaluate the hazard zones flooding in the Del Pato, San Lázaro, Venezuela and Los Incas gullies.

En este trabajo se presenta una aplicación práctica del uso de las tecnologías de la información y comunicación (TIC) en la gestión de riesgos de desastres debidos a precipitaciones extremas en regiones urbanas. El objetivo es plantear, a partir del caso de estudio del deslizamiento del cerro del Chiquihuite, una de las formas en las que se puede aprovechar la información del Observatorio Hidrológico del Instituto de Ingeniería de la Universidad Nacional Autónoma de México (OH-IIUNAM) para mejorar la gestión de desastres generadas por precipitaciones extremas. En el caso de estudio, se utilizan los datos del OH-IIUNAM para el análisis temporal y espacial de las tormentas que se presentaron en la Zona Metropolitana del Valle de México entre el 1 y 9 de septiembre de 2021; también se considera el sismo que ocurrió el 7 de septiembre del mismo año. La conjunción de ambos fenómenos produjo un deslizamiento del cerro el 10 de septiembre de 2021, que provocó grandes daños en las viviendas y pérdidas humanas. En el análisis temporal realizado se encontró que las tormentas más importantes ocurrieron entre los días 1 y 8 de septiembre, destacando las tormentas de los días 6 y 7 en intensidad y precipitación acumulada. En cuanto al análisis espacial, se utilizó la interpolación IDW (interpolación de distancia inversa ponderada) para estimar la precipitación en toda la Ciudad de México (CDMX) en el periodo del 1 al 9 de septiembre, encontrándose que la zona del cerro del Chiquihuite fue una de las áreas donde cayó mayor cantidad de agua de lluvia.

Durante el proceso de coagulación dentro de una planta de tratamiento de agua potable (PTAP), para disminuir la turbiedad se usan polímeros sintéticos y orgánicos. La Moringa oleifera (MO), como coagulante natural, requiere usar una concentración y dosis óptima, a fin de reducir la mayor cantidad de turbiedad y evitar materia orgánica residual que requiera un tratamiento adicional. Es por ello que la investigación tuvo como objetivo determinar la eficiencia del uso de la MO, para la clarificación del agua de la quebrada Taczanapampa de la ciudad de Huancavelica, Perú. Se utilizaron las partículas molidas de las semillas de la mencionada planta, evaluando diferentes dosis y concentraciones para encontrar la óptima en la remoción de la turbidez en el agua, procedimiento que se realizó con la prueba de jarras del laboratorio. Los modelos de regresión validaron el comportamiento de la MO en ecuaciones. El primer modelo determinó la dosis óptima y el segundo modelo la concentración óptima en las condiciones de la investigación. Los resultados de la dosis óptima se obtuvieron en dos rangos: con turbiedades menores a 50 unidad nefelométrica de turbidez (UNT) de 10 a 50 mg/l, también entre 50 y 150 UNT de 30 a 100 mg/l; y la concentración óptima para turbiedades menores a 150 UNT se encuentran en un rango de 2 a 3 %. Los resultados se consideran favorables para su uso y amigables con el ambiente.

En la cuenca Guantánamo-Guaso, ubicada en la región oriental de Cuba, los recursos hídricos están sometidos a fuertes presiones debido al desarrollo poblacional, agropecuario e industrial, constatándose el deterioro del ecosistema con la consiguiente afectación de sus bienes y servicios, e implicaciones en el abasto de agua. El objetivo de esta investigación fue determinar el potencial hídrico superficial de la cuenca Guantánamo-Guaso a partir de la evaluación de la cantidad y calidad de sus recursos hídricos superficiales. Se utilizaron los datos de precipitaciones de 60 equipos pluviométricos localizados en el área, obteniéndose el mapa isoyético para determinar el escurrimiento medio hiperanual, considerando que la cuenca no posee estaciones hidrométricas. El potencial hídrico superficial total (232.521 hm3) resultó ser reducido en un 28 % por requerimientos ambientales y en un 19 % por la calidad del agua. Los problemas asociados con la calidad de agua se relacionan con la existencia de fuentes contaminantes; mientras que la disponibilidad está influenciada, en el último decenio, por intensas sequías, cuyos efectos se han agravado en la última década como consecuencia de los efectos del cambio climático. Esta investigación constituye un punto de partida para la toma de decisiones en la gestión hídrica de la cuenca Guantánamo-Guaso, a fin de garantizar el abasto de agua para diferentes propósitos.

La agricultura convencional depende de la aplicación de fertilizantes con el fin de lograr mayores rendimientos; sin embargo, es necesario encontrar un equilibrio entre sus beneficios y las alteraciones que pudieran producir a los ecosistemas. Organizaciones internacionales regulan su uso y comercialización teniendo en cuenta la eficacia y seguridad. IHPLUS®, producido por la Estación Experimental de Pastos y Forrajes “Indio Hatuey” (Cuba), ha mostrado ser efectivo en diferentes cultivos y es objeto en este estudio evaluar los efectos sobre la calidad del agua en el bioindicador Poecilia reticulata. Los peces fueron expuestos al producto, en régimen estático durante 96 h, a la concentración efectiva en la agricultura (6 %) o diluido hasta 106 UFC/ml según recomienda la EPA OPPTS 885.4000. Asimismo, se incluyó un grupo tratado con el producto al 6 %, pero esterilizado y un grupo control que no recibió tratamiento alguno. Se observaron durante 30 días posinoculación y se evaluó el peso, la mortalidad y otros efectos subletales. Posteriormente, se determinó la concentración letal media (CL50) y la influencia del pH sobre la mortalidad de los peces. Se pudo comprobar que al 6 % provocó eventos clínicos adversos y efecto letal en el biomodelo. Las lesiones histopatológicas se corresponden tanto para el producto activado como para el inactivado. La CL50 fue de 3.19 %, asociándose la toxicidad al pH ácido y no a la carga microbiana presente en el bioproducto. Se concluye que IHPLUS® es seguro para Poecilia reticulata a concentraciones inferiores al 3 %.

El objetivo es analizar el consumo de agua embotellada en México con miras a una economía circular. El documento evalúa las tasas de consumo de agua embotellada y los factores causales clave. Además, compara el rol que juegan los sectores público y privado en la exacerbación de la demanda de agua embotellada. El documento implementó una revisión sistemática que identificó artículos principalmente de las bases de datos Web of Science y Scopus del 1 de noviembre al 31 de diciembre de 2022. Se utilizaron tres estrategias para el proceso de búsqueda, incluida la introducción de palabras de texto libre, la implementación de operadores booleanos y búsqueda de citas. La revisión sistemática se realizó de acuerdo con la declaración/metodología PRISMA. Cuarenta y ocho artículos fueron identificados después de la búsqueda completa. Los resúmenes indican que el consumo de agua embotellada es alto en México debido al suministro de agua potable convencional por debajo de la media. La mayoría de los clientes mencionaron razones organolépticas y de salud como factores clave que influyeron en su preferencia por el agua potable embotellada. Por el contrario, la demanda de agua embotellada contribuye a las botellas con alto contenido de tereftalato de polietileno, lo que contribuye a la degradación ambiental. La implementación de la economía circular puede reducir los efectos negativos asociados a través de estrategias de reducción y optimización. Se agruparon los hallazgos de varios artículos mientras se definieron las brechas clave y las áreas de mejora. El documento es fundamental para salvar la escasez de conocimiento sobre la economía circular y su aplicación en la industria del agua, al tiempo que proporciona recomendaciones para los responsables de la formulación de políticas.

En la perspectiva de la gestión integral del agua, el manejo de recursos de uso común y la sustentabilidad de los sistemas de riego, el presente trabajo analiza el diseño y funcionamiento de los módulos de riego del Distrito de Riego 061 Zamora (DR 061), y muestra aportes no considerados de los usuarios del riego en el mantenimiento de los sistemas. El diseño y funcionamiento organizativo se analizó en sus dimensiones de gobierno, administración y operación. Las aportaciones de los usuarios y ejidos se determinaron con base en una muestra de cuatro canales, donde se identificaron las tareas que realizan los módulos y los usuarios para el acceso al agua y el mantenimiento. Los resultados muestran que existe un manejo centralizado burocrático en las tareas de distribución del agua y mantenimiento de la red principal, reelección permanente de autoridades de los módulos, diseño de cuotas de riego no consensuadas con los usuarios, morosidad en la recuperación de cuotas y falta de transparencia en la rendición de cuentas. Se calculó que las aportaciones de los usuarios superan 13 veces lo invertido por los módulos, pero sus aportes no son considerados para la participación directa en la toma de decisiones, y en el gobierno y la administración de los módulos, lo cual muestra limitaciones y deficiencias en el diseño organizativo por módulos que debilitan la autogestión y sostenibilidad de estas organizaciones.

Recientemente se ha evaluado el uso de lodos residuales de aluminio (lodos-Al) de plantas de tratamiento de agua potable para la eliminación de fósforo y ha demostrado ser altamente eficiente. Sin embargo, la mayoría de los estudios se han realizado utilizando agua sintética. Solo unos pocos trabajos han aplicado este método a aguas residuales (AR) reales y ninguno de ellos ha sido probado en modo continuo, como paso de pulido, en una planta de tratamiento de aguas residuales (PTAR) descentralizada a escala piloto. Este trabajo tuvo como objetivo evaluar el desempeño de un filtro sumergido empacado con un lecho de lodos residuales de Al como sistema de pulido para la eliminación de fósforo en una PTAR descentralizada a escala piloto. El estudio determinó a escala de laboratorio la capacidad de eliminación de fósforo mediante pruebas discontinuas y continuas, utilizando aguas residuales tanto sintéticas como reales, y se evaluó el efecto del tiempo de retención. Con base en los resultados, se construyó, implementó y evaluó un filtro sumergido de lodos de Al (filtro lodos-Al) a escala piloto como paso de pulido para el efluente de una PTAR descentralizada. Los resultados mostraron que durante las pruebas continuas con AR real, la capacidad de eliminación de fósforo fue de 2.55 mg P-PO43-∙g-1 por gramo de lodo-Al utilizando un tiempo de retención de 120 min. El filtro de lodos Al como sistema de pulido presentó una eficiencia de remoción promedio de 94 ± 8 % y una concentración de efluente inferior a 0.50 mg P-PO43-∙l-1 durante los primeros 20 días operativos. Durante los siguientes 17 días, el sistema eliminó 85 ± 9 % en promedio, mostrando una concentración de efluente inferior a 1.0 mg P-PO43-∙l-1. A partir del día operativo 32, la eficiencia de remoción fue de 63.6 ± 10.7 %, con una concentración promedio de efluente de 2.20 ± 0.39 mg P-PO43-∙l-1.

El objetivo de esta investigación fue analizar el entramado político del sistema de abasto de agua de uso doméstico del municipio de Oaxaca de Juárez desde su fundación en 1523 hasta su conformación metropolitana actual. El estudio tiene por base la hidropolítica, bajo un enfoque en la captación, abastecimiento y control. La metodología cualitativa se apoyó en un análisis explicativo del manejo del agua municipal, sustentado en fuentes primarias, como archivos históricos, documentos oficiales y estadísticos, así como artículos e investigaciones académicas que aluden al proceso historiográfico del abastecimiento de agua. Se identificaron cinco procesos hidropolíticos clave: 1) el modelo monárquico de abasto frente a la perspectiva mesoamericana de uso (1523-1821); 2) la edificación hidráulica municipal (1755-1912); 3) legislaciones, acuerdos y conflictos intermunicipales (1821-1930); 4) conformación interurbana del sistema de agua municipal (1858-actualidad), y 5) metropolización del servicio de agua (1983-actualidad). Se concluye que el sistema de agua de Oaxaca y su edificación hidráulica se han desarrollado a partir de procesos incidentales de control en la subcuenca del río Atoyac-Oaxaca, generando conflictos, tensiones y arreglos que transgredieron la esfera municipal hasta conformar una entidad metropolitana del agua.

El oleaje de mar de fondo plenamente desarrollado que alcanza Canarias procedente del hemisferio sur, caracterizado por alturas de ola moderadas y periodos largos, es generalmente difícil de distinguir. Sin embargo, las condiciones extraordinarias de calma permitieron a la boya de Puertos del Estado en el sur de Tenerife detectarlo de forma continuada durante el mes de agosto de 2023. En este trabajo se estudia la naturaleza dispersiva y se estima la distancia recorrida por el oleaje de tipo swell que llegó a Canarias procedente del sur en ese periodo. Contrastando estos resultados con los datos del modelo Wavewatch III del NOAA, se infiere que el área de generación de este oleaje se sitúa en la zona extratropical del Atlántico Sur, donde la actividad ciclónica es notable a lo largo de todo el año, y más aún durante el invierno austral.

El principal objetivo de este estudio es el análisis de la movilización de sedimento durante la avenida controlada del 5 de mayo de 2022 en el curso bajo del río Ebro desde la presa de Ribarroja. Durante este evento, se realizó una campaña de ensayos incluyendo aforo de caudales y medidas de turbidez y concentración de sedimentos en suspensión. Esta información ha permitido simular numéricamente el curso bajo del río Ebro desde la presa de Flix hasta su desembocadura con el modelo Iber, modelo euleriano 2D basado en el esquema de los volúmenes finitos de primer orden. Para ello se ha empleado el módulo de transporte de sedimentos en suspensión que resuelve la ecuación de advección – difusión, que emplea el modelo de erosión y sedimentación de Van-Rijn y resuelve la conservación de masa de Exner para estudiar la evolución del lecho. Los resultados de la modelización numérica son coherentes con la campaña de ensayos y validan el modelo Iber para analizar el transporte de sólidos en suspensión en la zona de estudio.

La preocupación por la sostenibilidad y la reducción del consumo energético ha impulsado la utilización de la energía solar para accionar las bombas utilizadas para riego agrícola. La energía capturada por los paneles solares es variable a lo largo del tiempo, por lo que es necesario modificar el funcionamiento de las bombas para ajustarse a la energía disponible. El presente trabajo plantea una metodología que utiliza las leyes de la semejanza hidrodinámica de manera completa sin simplificaciones para optimizar el número de bombas funcionando en cada instante y la potencia total instalada en el aprovechamiento fotovoltaico. La utilización de la hipótesis de homología muestra que en la mayoría de los casos la potencia instalada sería insuficiente. Por el contrario, la metodología propuesta proporcionaría diseños adecuados en todos los casos. El artículo se completa con la aplicación a un caso de estudio para mostrar la adecuación del método a una instalación de bombeo a balsa. Por último, se ha realizado un estudio básico de la viabilidad económica obteniendo como resultado un periodo de recuperación de la inversión en torno a los 7 años.

Las inundaciones son una de las catástrofes naturales más comunes a nivel mundial, y acarrean impactos socioeconómicos severos, incluyendo la pérdida de vidas humanas. Este estudio evalúa la respuesta hidráulica del entorno de la autopista M-30 de Madrid contra eventos de inundación extremos del río Manzanares mediante el uso de una metodología de análisis multivariante. La comparación de los resultados obtenidos a través de esta nueva metodología con los derivados del enfoque tradicional, basado en estadística univariada y sin usar generación sintética, resalta la limitación de los métodos convencionales para estimar periodos de retorno. Esto enfatiza la necesidad de integrar nuevos enfoques en el diseño de infraestructuras para gestionar de manera más efectiva su respuesta frente a inundaciones.

Este estudio se centra en la gestión de sistemas de drenaje urbano capaces de reducir la contaminación de las aguas pluviales. Se enfoca en la eliminación de níquel (Ni), presente en las aguas de escorrentía urbana, debido a su toxicidad y posible acumulación en los organismos vivos. Se plantean ensayos en columnas de laboratorio utilizando Filtralite como material filtrante. Se emplea el módulo HP1 para calibrar un modelo que analiza el transporte y eliminación de este metal pesado. Se observa que la interacción entre el material y la disolución contaminada aumenta el pH, lo que provoca la precipitación de hidróxido de Ni en los primeros nodos de la columna. Los resultados indican que la concentración del contaminante en la disolución depende directamente del pH. En condiciones ácidas, el Ni permanece en la disolución, pero a partir de un pH de 7.5, comienza su eliminación, hasta desaparecer para valores superiores a 11.

The contestation and appropriation of water are global issues. Capturing control of water sources determines how and by whom water will be used. This paper examines how water grabbing occurs through both water infrastructures and institutions. Building on the concepts of 'infrastructural violence' and 'accumulation by dispossession', I investigate the mechanisms employed by bottled-water companies to grab water and hide the scale of grabbing, resulting in the dispossession of local farmers from the water sources they have used for centuries. Drawing on ethnographic research in Ağlasun, a rural town in southwest Turkey, my findings reveal two main insights. First, water grabbing occurs through clientelism, bending of the rules, and ambiguities in water governance legislation. Second, water grabbing is facilitated by infrastructural changes, such as the fencing off of water sources and the forced imposition of water-saving agricultural technologies. Understanding the various institutional and infrastructural processes through which water grabbing occurs helps clarify the conditions necessary for more just and equitable water governance. The paper concludes by highlighting the crucial role of locally embedded institutions and collective action in securing access to water.

Many cities around the world are facing the challenges of freshwater decline and groundwater degradation, compounded by population growth. In the southwestern United States, these challenges are amplified. In that region, many growing cities depend on water from the Colorado River Basin, which is faced with aridification and record-low surface water supplies. Despite these unprecedented trends in Colorado River flows, however, many basin cities are enhancing their water security through a combination of supply diversification and water conservation. We draw from key academic and practitioner studies to better understand which conservation strategies are employed, how water providers evaluate the effectiveness of these strategies, and what role urban water conservation has played in the Colorado River Basin. Our examination of the contributions and limitations of urban water conservation under Colorado River Basin drought conditions reveals how the political dimensions of urban water conservation influence the ability to fully realise the potential of conservation in broader basin governance and sustainability. We call for improved assessment and monitoring of conservation efforts, advancement of holistic approaches, and the addressing of key political and equity dimensions as ways to improve urban water conservation efforts and, more realistically, situate them in the context of basin wide sustainability.

The notion of water justice is increasingly invoked by both scholars and activists working to address issues of inequity in water governance. However, water justice means different things to different people, which can present challenges when building alliances among diverse actors. In this paper, we examine these dynamics in the context of unlikely alliances formed among environmental, ranching, and Indigenous actors in response to ruralto-urban water transfer projects in the arid Great Basin region of the western United States. Through more than 60 interviews across two cases in eastern California and eastern Nevada, we find that though these actors aligned in their opposition to projects they viewed as unjust, they had different views of what justice would look like. We discuss their diverse visions of water justice in relation to notions of distributive, procedural, restorative, and transformative justice. While many of these visions overlapped and complemented each other, others were more starkly divided by their orientation towards the current state of water governance, with some seeking to protect it and others seeking to transform it. Building alliances thus required some to strategically focus on the common ground around protecting existing water allocations and systems of accountability, while separately pursuing broader visions of repairing past harms and transforming underlying systems. This research demonstrates that understandings of water justice are diverse and dynamic and that they shape and are shaped by alliance-building. It underscores the methodological value of asking people to articulate not only how they ally against injustices but also what they would consider a just outcome and how they approach collaboration when there are different visions of water justice.

Although an extensive literature focuses on gender and water, fewer studies focus explicitly on intrahousehold power dynamics and their consequences. This paper aims to understand the intrahousehold power dynamics that influence decisions such as who collects water from what source and how water is allocated across activities. Drawing on the rich intrahousehold literature from economics, we demonstrate how it would strengthen our understanding of the impacts of water policy and interventions. A review of intrahousehold bargaining models suggests that it is important to consider how policies and interventions in the water sector may affect the outside options of household members and thus shape their bargaining power. Social norms, property rights and water infrastructure all influence household members’ bargaining power and shape the context within which household decisions are made. Analysing intrahousehold dynamics for water needs to go beyond just considering the dynamic between the spouses; it also needs to consider others in the household who may provide labour for fetching water and who require water for their personal care and productive livelihoods.

In response to capitalist territorial transformations, humans’ predatory subjection of nature, and worldwide socio-environmental injustices, a diverse set of eco-centric, other-than-human, and indigenous worldview-inspired perspectives have emerged in water debates and practices. Rights of Nature (RoN) and Rights of Rivers (RoR) approaches are examples of this. But while these 'river ontological turns' hold exciting conceptual and political potential, they also invite critical reflection. Proponents often advance these new ontological perspectives and initiatives as being more 'real' and 'natural' than what came before. We challenge this notion by conceptualising such perspectives, similar to all ontological framings, as politically contested entrances to imagining and ordering the real. We argue that these new and alternative ontological understandings of the world – and their related initiatives – are politically produced, culturally enacted, and strategically mobilised. In effect, they contribute to the constitution (or contestation) of particular power relations. Focusing specifically on river debates, we identify and explore the following fields of contention that arise in and from alternative eco-centric and nonhuman ontological turns: the god-trick; naturalisation; de-centring the human; mystifying/essentialising indigeneity; and subjectification-through-recognition. By discussing these fields of contention, we call for a repoliticisation of the recent river (and other related) ontological turns, their underlying assumptions, and conceptualpolitical tendencies. Such critical scrutiny can contribute to enriching local/global struggles for riverine environmental justice.

Solidarity as a moral appeal has made a regular appearance in water policies, but the concept has rarely been theorised in relation to water governance from a socio-political perspective. As a consequence, the real-life sociological and political underpinnings of hydrosolidarity have remained underexplored. This has limited its conceptual elaboration, analytical use and practical applicability in critical water governance theory and practice. Recent developments in sociopolitical research on solidarity have the potential to make up for this gap. This literature broadly defines solidarity as the willingness or moral obligation to share and redistribute material and immaterial resources. It emphasises solidarity as a situated praxis that is influenced by, and simultaneously constitutive of, social structures. Drawing from this literature, we identify four perspectives through which theories of hydrosolidarity can be enriched: first, an exploration of the sociopolitical foundations of hydrosolidarity as situated praxis; second, an expansion of the spatial imaginaries of hydrosolidarity; third, a broader understanding of the role of infrastructures for hydrosolidarity; and, finally, a more thorough theorising of hydrosolidarity beyond the human. These four perspectives, we argue, open up new lines of empirical inquiry on collective water governance.

In the Republic of South Africa (RSA), reforms to existing and new water allocations have been aimed mainly at redressing the racial injustice of the past. Such reforms, however, have failed to materialise in the citrusproducing region of the Western Cape. This paper argues that the emergence of a strong Global Production Network (GPN) of citrus export at the time of rolling out of the water reforms has contributed, and continues to do so, to the failure of these reforms. The high quality and quantity requirements imposed by the GPN, we argue, necessitated the use of precision fertigation, which acted as an entry barrier to Western Cape citrus products. With access to specialised precision fertigation networks, the landed (white) commercial farmers were able to forge long-lasting relationships of trust and quality with the retailers of the citrus GPN and thus gain and maintain privileged access to it. Their strong position in the citrus GPN enabled three strategies of new water access to emerge, that are exclusively available to the established (white) commercial farmers, namely: (1) using water illicitly; (2) attaining a controlling stake in Black Economic Empowerment (BEE) partnerships; and (3) through access to the network of water consultants. New water access consolidates existing positions of growers in the GPN, making the position in the GPN and water expansion a mutually reinforcing phenomena. High GPN entry barriers have advantaged established commercial farmers and effectively impeded the intended introduction of more equitable water reforms in the region.

The article reviews international acts in the field of combating climate change (United Nations Framework Convention on Climate Change, Kyoto Protocol and Paris Agreement), identifies the main trends in the field of carbon regulation: emissions quoting; implementation of climate projects; introduction of greenhouse gas reporting and expansion of the legislative framework. A comparative analysis of the national legislation in force in the Republic of Belarus and the Russian Federation is carried out, its conditional classification is considered with the allocation of carbon regulation instruments being applied, viz. the market ones, the restrictive ones, the supporting ones and the auxiliary ones. The regulation of greenhouse gas emissions should include a wide range of activities and cannot be reduced solely to restrictive instruments. Market instruments include the national emissions trading system, international voluntary markets and instruments of international cooperation, while restrictive instruments include the introduction of carbon taxes, quotas, and mandatory carbon reporting. Among the examples of supporting instruments subsidies, targeted financing and tax preferences, as well as information policy may be noted. Auxiliary instruments include methodologies for quantitative assessment of greenhouse gas emissions and uptake, carbon reporting standards and tools for verification of reporting on greenhouse gas emissions, legislated possibility of implementing climate projects. The normative national regulation regarding the accounting of greenhouse gas emissions is considered, the categories of emission sources and greenhouse gases whose emissions are subject to accounting are identified. It is important to note that the legislation on greenhouse gases in the Republic of Belarus and the Russian Federation, as well as around the world, has not been finalized and is in the process of formation.

Due to the growth of “green” energy, the need to regulate the load on large power systems, and the development of electric transport, electricity storage systems (ESS) are increasingly, being used in the world. Conceptual documents have been developed in the Republic of Belarus and the Russian Federation stating the need to modernize the regulatory framework for the use of ESS, create scientific support for the development of ESS technologies, centers of competence and of the implementation of pilot projects. This article provides an example of calculating the economic effect of using ESS at an industrial enterprise. A methodology is proposed that can be used to develop standardized methods for calculating the economic effect of using ESS at enterprises and in local energy systems of consumers of various types. The main functions performed by the ESS at the enterprise are characterized. The features of calculating the economic effect of performing these functions under the conditions of the statistical nature of the load regime of the enterprise are considered. Calculations of the simple payback period for investments in the installation of an ESS for an enterprise with several options for payment terms for electricity are given. It is shown that the economic result of using ESS significantly depends on both the pricing conditions and load schedules of the enterprise, as well as on specific requirements for the quality and reliability of power supply and should be evaluated individually in each case.

One of the directions of development of the electric power industry is decentralization, aimed at improving the reliability of energy supply, reducing losses during transmission of electric energy and ensuring energy independence of consumers. It is possible to simulate decentralized power systems, including distributed generation facilities, by implementation of multi-agent systems that allow solving design and control problems taking into account the needs of each participant in the process of production, transmission, distribution and consumption of electricity. The development of distributed generation using a multi-agent approach requires the creation of models for assessing the technical and economic efficiency of decisions made by each agent, both at the strategic and tactical levels. The strategic decisions of agents related to distributed generation include, among other things, the creation of power facilities and power plants based on renewable energy sources. An important factor for making such decisions is the estimation of the capacity factor. However, currently there are no models for its estimation with high reliability. The present paper proposes a new algorithm for estimating the capacity factor for the entire territory of a certain administrative unit and a model for its forecasting based on climatic and geographical parameters. The study was conducted on a data sample of 221 generation facilities (solar and wind power plants) in four oblasts (regions) of the Russian Federation. It has been determined that the capacity factor can be forecasted with a mean error within 4 % for photovoltaic power plants and 9 % for wind power plants. Therefore, it is possible to use the developed algorithm and model both in decision support systems when choosing the location of this types of power plants, and in systems that model the development of power systems using a multi-agent approach.

The paper presents an experimental study of an assembly of five stages of an electric centrifugal pump (ECP) installation, the flow part of which is modified according to the principles of biomimetics, namely using the “lotus leaf effect”. The object of the study was a 5A-35 ECP. The surfaces of the blade systems of impellers and guide devices of stages 5 A-35 were hydrophobized using the method of applying surfactant layers. The degree of impellers hydrophobicity was estimated by the wetting angle average value measured by three drops at three different points on the impeller surface. The impellers surface roughness under study was determined by the arithmetic mean profile deviation Ra and the profile height irregularities Rz. The issues related to the surfactant coating modification effect salt deposition and corrosion were studied. For this purpose, the surfaces of the original and modified impellers were subjected to intensive forced salt deposition as a result of prolonged exposure to saline solution. The conclusion about the samples corrosion resistance degree was made by changing their mass, which was due to the salt deposits formation during 15 hours of stay in solution, as well as using the drop method. Both methods have shown that the surfactant coating can serve as a salt deposition inhibitor, and the pump impeller modified by it has increased corrosion resistance. Thus, during comparative tests, a smaller mass of salt was deposited on the modified impeller sample during 15 hours of exposure in saturated saline solution than on the original sample. This indicates that the surfactant layer prevents the salt deposits fixation on the working surfaces of the pump stage. On the modified sample examined by the drop method, the indicator color changed in 20 minutes, and on the original one – in 2 minutes. Experimental studies have been carried out, during which the operation energy parameters of a five stages 5A-35 pumping package with initial and modified surfactant-coated impellers have been determined. The studies have shown a 2 % increase in efficiency in the pum-ping package of stages with modified impellers. The results of the study can be useful in the oil production, chemical industry, as well as in the housing and communal services sector.

Solar energy is one of the most important and promising energy sectors in the world. Batteries that convert sunlight into electrical energy could become a replacement for traditional carbon-based energy sources. Vertical thin-film solar batteries are one of the new approaches to solar energy generation. The vertical configuration of solar panels provides maximum absorption of sunlight throughout the day. This orientation allows the batteries to capture solar energy even at low angles of incidence of the sun’s rays, which prolongs their operating time and improves the efficiency of electricity production. In this work, the authors proposed a three-dimensional model of a vertically oriented solar battery, as well as they calculated and evaluated the temperature characteristics and the efficiency obtained under conditions of changing ambient temperature. Herewith the power densities of concentrated solar radiation with maximum values from 1 to 10 kW/m2 were varied. The distribution of the maximum values of the surface temperature of the solar battery has been studied. Also, the dependences of the maximum values of the solar battery temperature and the temperature gradient inside it, as well as the dependences of the minimum and maximum values of the heat flux from the solar battery surface on the time of day in the middle of January and July have been studied and plotted. As the calculations have shown, the maximum values of the temperature gradient inside the solar battery in January are ~47–50 % higher than in July. The potential difference, generated by the battery, reaches its maximum values from 11 a.m. to 4 p.m. both in January and July. The use of vertical thin-film solar batteries will improve the power generation efficiency and lower operating costs by reducing the influence of dust, rain and snow.

The development of the industrial sector and the increase in production capacity have a positive effect on the economic situation of the country, but not on environmental safety. Insufficiently purified and polluted wastewater is constantly discharged into water sources, the amount of which directly depends on the industrial development of the region. Thus, the anthropogenic load on the Oka River affects the composition of water in the source, there are often bursts of instantaneous emissions, as well as the flowering of phytoplankton in the summer. The latter further significantly reduce the efficiency of water purification to drinking quality. Therefore, the development of technologies that will be able to maintain purification at the required level is an urgent task. The article presents the method of charcoalization, which allows to neutralize pollution in a short time and improve the water treatment quality. An industrial experiment of the developed technology was carried out at an operating water treatment plant with testing of two extreme do-sages of sorption material. The optimal dose of coal pulp was determined, the impact on significant purification performance was described, and the technological solutions have been developed to determine the point of coal pulp input and the dosage multiplicity. The conducted research has made it possible to expand knowledge in the field of drinking water preparation and to determine significant water parameters that are affected by the sorption purification method.

Abstract The utilization of geopolymer as a grouting material has gained significant attention in research and construction applications. Geopolymer grout is a type of binding material that differs from traditional grouts, typically based on Portland cement. Researchers have explored its effectiveness and potential applications in grouting processes, considering its unique properties and characteristics. In this paper, various studies employing and utilizing geopolymer as a grouting material are reviewed. The emphasis is on mixture design of geopolymer grout, physical property, chemical composition of geopolymer grout, rheological behavior of geopolymer grout such as yield stress (in case of Bingham fluid) and viscosity, and engineering properties such as compressive strength, expansion, shrinkage, etc.

Abstract The necessity of predicting geotechnical parameters in soft ground tunnelling is crucial for selecting the appropriate tunnel boring machine (TBM), evaluating the operating limit of earth pressure balance (EPB) machines’ parameters, and ensuring the safety and efficiency of TBMs during tunnel construction. In this research, various EPB operating parameters such as cutterhead torque, thrust force, chamber pressure, and cutterhead rotation speed (RPM) were utilized to estimate geotechnical parameters like friction angle (φ) and shear strength (τ) for engineering geological units ET1 to ET5 (fine-grained and coarse-grained soils) along the tunnels route, which serve as indicative units for the entire tunnels path. Statistical methods and computational techniques, namely support vector regression (SVR) and feed-forward neural network (FFNN), were trained using EPB operating parameters and geotechnical data from Tehran metro line 6—southern extension sector (TML-SE6) and the East–west section of line 7, Tehran metro project (TML-EW7). A comprehensive dataset comprising borehole logging results along the tunnel path was gathered, with 85% of the data randomly selected for training and the remaining 15% reserved for model testing. Various loss functions and statistical metrics were employed to evaluate the accuracy and precision of the method. The results of the proposed models demonstrate satisfactory and reliable accuracy of the approaches.