Hydraulic Potential Research Articles

Effect of Bed Material on Roughness and Hydraulic Potential in Filyos River

Seasonal changes, sea level rise, and global warming make flood events more frequent, which necessitates watershed management and efficient use of water resources. In this context, understanding the hydrodynamic behavior of basins is critical for the development of flood prevention strategies. The contributions of hydrological and hydraulic modeling techniques in this process are among the key determinants of sustainable water resources management. The Filyos Sub-Basin, located in the Western Black Sea Basin, stands out as one of the regions where flood risk assessment is a priority, as it has two important floodplains. This study aims to analyze the flood risk in the Filyos River Sub-Basin with hydraulic modeling methods, and to determine the Manning roughness coefficient. In the study, the parameters affecting the roughness of the river bed were analyzed using the Cowan method, and the effects of vegetation on river bed resistance were evaluated in the laboratory environment. Flood simulations were carried out for four different flow rates (Q1000, Q500, Q100 and Q50) using the HEC-RAS model, and the performance of flood protection structures were analyzed. The findings show that a significant portion of the existing protection structures are unable to meet the potential flood flows, which can cause serious damage to residential and agricultural areas. In basins with limited historical discharge data, such as the Filyos River, these findings provide important contributions to sustainable water resources management and regional planning processes. The results of the study serve as a reference for flood risk assessment, not only for the Filyos River Basin, but also for other basins with similar hydrodynamic characteristics. It is envisaged that future research, supported by larger data sets, can improve the accuracy of flood simulations. Furthermore, the Cowan method and HEC-RAS model used in this study are expected to contribute to strategic planning and engineering solutions to minimize flood risk in other watershed management projects. In future studies, we plan to further develop methodological approaches for determining the roughness coefficient, and to address applications to increase the effectiveness of flood protection structures.

Reactivity of air granulated basic oxygen furnace steel slag and its immobilization of heavy metals

Air granulation of basic Oxygen furnace slag can improve its hydraulic potential to enhance recycling potential. The hydration behaviour of the slag has been investigated via isothermal calorimetry, QXRD, and TG/DTG analysis. The air granulated slag exhibited improved early-age hydration and led to the formation of C–S–H, hydrogarnet, and hydrotalcite phases. The slag reactivity is controlled by the dissolution of SiO2 and Fe2O3 bearing phases as observed by SEM-EDX-based PARC analysis and the hydration degree reaches up to 41% after 28 days curing. The hydrated slag features an improved immobilization of V and Cr as confirmed by ICP-OES analysis.

Legendre Galerkin spectral collocation least squares method for the Darcy flow in homogeneous medium and non-homogeneous medium

The Darcy's equation consists of the mass conservation equation and the Darcy's law that involves the hydraulic potential (or called pressure) and the fluid velocity, which governs the flow of an incompressible fluid through a porous medium. In this paper, we investigate the Legendre Galerkin spectral collocation least squares method for approximating the problem of Darcy flow in homogeneous medium and non-homogeneous medium, respectively. The proposed scheme can be solved the approximate solutions of the hydraulic potential and the average velocity of the fluid simultaneously. A symmetric positive definite coefficient matrix of the corresponding linear algebra equation is obtained by applying our scheme. Numerical examples are presented to validate the efficiency and accuracy of the proposed scheme.

On the need to account changes in hydraulic performance of worn-out metal water pipes

During the operation of metal water pipes made of steel and gray cast iron, a layer of internal deposits is formed, which changes the hydraulic potential of the pipes: the actual inner diameter, the actual speed of water movement and the actual pressure losses for resistance along the length (the actual hydraulic slope). These changes must be taken into account because the energy consumption of pumping units supplying drinking water to consumers located at a considerable distance from pumping units changes. A specific example shows how changing the hydraulic potential of worn pipes affects the energy consumption of pumping units that supply water to consumers.

Investigation on reuse of energy at a sewage treatment plant and payback period

AbstractThe reuse of energy is a topic currently being widely discussed around the world. This study analyzes the potential for energy reuse in treatment plants. Sewage Treatment Plants are responsible for treating the water present in the sewers of cities. The treated water returns clean to the river, and generally, the place of discharge has a high height and flow rate that can be harnessed for the generation of electric energy. This work investigates the feasibility of installing a Micro Hydroelectric Plant in the Treatment Station of the Uberaba River in Brazil. Hydraulic potential and investment analysis were used as viability criteria. For the study, a height of 6 m and an average flow rate of 0.465 m3/s were considered, which could generate about 22.51 kW using a Bulb water turbine. This power represents a return of US$1651.26 per month from the generation of electric energy. The estimated installation cost was US$32,966.73, and the payback period was found to be less than 2 years. There are 702 sewage treatment plants in Brazil alone, and hypothetical analyses were performed with flow rates ranging from 0.2 to 1 m3/s and heights ranging from 1 to 9 m. Motivating results with payback periods of less than 4 years were obtained for numerous hypothetical situations, which demonstrates the feasibility of installing Micro Hydropower Plants and achieving savings in the sewage treatment system.

Causes and consequences of changes in the values of hydraulic characteristics of metal water supply and sanitation networks during their operation

Purpose: It consists in carrying out a comparative analysis of the values of the characteristics of the hydraulic potential of metal pipelines used in assessing the energy consumption of pumping units installed on pipelines with different thickness of the layer of internal deposits.
 Methods: The reasons for changing the values of hydraulic characteristics of metal pipelines during their operation are developed in tabular form. A concrete example shows the change in the values of the characteristics of the hydraulic potential of pipes with different thickness of the layer of internal deposits included in the calculated dependence for determining the actual energy consumption of pumping units.
 Results: It is proposed to develop for the entire range of manufactured steel pipes and pipes made of gray cast iron, a scale of maximum permissible values of the thickness of the layer of internal deposits, according to which a decision should be made to continue or stop the operation of pipe wires.Conclusion: To recommend, based on the hydraulic calculation of the characteristics of the hydraulic potential of pipes for the given example, minimizing the use of steel and cast iron pipes made of gray cast iron in projects of water supply and drainage networks. When operating metal pipelines, take into account the dynamics of changes in the energy consumption of pumping units with different thickness of the layer of internal deposits.

The Subglacial Lake That Wasn't There: Improved Interpretation From Seismic Data Reveals a Sediment Bedform at Isunnguata Sermia

AbstractRadio Echo Sounding (RES) surveys conducted in May 2010 and April 2011 revealed a 2 km2 flat area with increased bed reflectivity at the base of Isunnguata Sermia at the western margin of the Greenland Ice Sheet. This flat reflector was located within a localized subglacial hydraulic potential (hydropotential) minimum, as part of a complex and elongated trough system. By analogy with comparable features in Antarctica, the initial interpretation of such a feature was a potential subglacial lake. In September 2013 a co‐located seismic survey revealed a 1,750 m by 540 and 37 m thick stratified lens‐shaped bedform at the base of a subglacial trough system. Amplitude Versus Angle (AVA) analysis yields a derived reflection coefficient R = 0.09 ± 0.14 indicative of consolidated sediments possibly overlain by dilatant till. The bed and flank on the northern side of the trough consist of unconsolidated, possibly water‐bearing sediments with R = −0.10 ± 0.08, whereas on the southern side it consists of more consolidated material. We interpret the trough as a key component of the wider subglacial drainage network, for which the sediments on its northern side act as a localized water‐storage reservoir. Given the observation of seasonally forming and rapidly draining supraglacial meltwater lakes in this area, we interpret the lens‐shaped bedform as deposited by episodically ponding meltwater within the subglacial trough system. Our results highlight the importance of transient subglacial hydrological and sedimentological processes such as drainage events for the interaction of ice sheets and their substrates, to understand ice dynamics in a warming climate.

A QGIS -plugin for gully erosion modeling

Gully erosion affects the landscape and human life in many ways, including the destruction of agricultural land and infrastructures, altering the hydraulic potential of soils, as well as water availability. Due to climate change, more areas are expected to be affected by gully erosion in the future, threatening especially low-income agricultural regions. In the past decades, quantitative methods have been proposed to simulate and predict gully erosion at different scales. However, gully erosion is still underrepresented in modern GIS-based modeling and simulation approaches. Therefore, this study aims to develop a QGIS plugin using Python to assess gully erosion dynamics. We explain the preparation of the input data, the modeling procedure based on Sidorchuk’s (Sidorchuk A (1999) Dynamic and static models of gully erosion. CATENA 37:401–414.) gully simulation model, and perform a detailed sensitivity analysis of model parameters. The plugin uses topographical data, soil characteristics and discharge information as gully model input. The plugin was tested on a gully network in KwaThunzi, KwaZulu-Natal, South Africa. The results and sensitivity analyses confirm Sidorchuck’s earlier observations that the critical runoff velocity is a main controlling parameter in gully erosion evolution, alongside with the slope stability threshold and the soil erodibility coefficient. The implemented QGIS plugin simplifies the gully model setup, the input parameter preparation as well as the post-processing and visualization of modelling results. The results are provided in different data formats to be visualized with different 3D visualization software tools. This enables a comprehensive gully assessment and the derivation of respective coping and mitigation strategies.

Subglacial hydrology from high-resolution ice-flow simulations of the Rhine Glacier during the Last Glacial Maximum: a proxy for glacial erosion

Abstract. At the Last Glacial Maximum (LGM), the Rhine Glacier complex (Rhine and Linth glaciers) formed large piedmont lobes extending north into the Swiss and German Alpine forelands. Numerous overdeepened valleys there were formed by repeated glaciations. A characteristic of these overdeepened valleys is their location close to the LGM ice margin, away from the Alps. Numerical models of ice flow of the Rhine Glacier indicate a poor fit between the sliding distance, a proxy for glacial erosion, and the location of these overdeepenings. Calculations of the hydraulic potential based on the computed time-dependent ice surface elevations of the Rhine Glacier lobe obtained from a high-resolution thermo-mechanically coupled Stokes flow model are used to estimate the location of subglacial water drainage routes. Results indicate that the subglacial water discharge is high and focused along glacial valleys and overdeepenings when water pressure is equal to the ice overburden pressure. These conditions are necessary for subglacial water to remove basal sediments, expose fresh bedrock, and favor further erosion by quarrying and abrasion. Knowledge of the location of paleo-subglacial water drainage routes may be useful to understand patterns of subglacial erosion beneath paleo-ice masses that do not otherwise relate to the sliding of ice. Comparison of the erosion pattern from subglacial meltwater with those from quarrying and abrasion shows the importance of subglacial water flow in the formation of distal overdeepenings in the Swiss lowlands.

Convective Versus Conductive Heat Flow in The Central Alberta Part Of The Western Canada Sedimentary Basin

Alberta, Canada, T6H 5X2. A detailed study of the hydrogeological and geothermal regimes in the Phanerozoic sequence of the Western Canada Sedimentary Basin was carried out for the Swan Hills and Cold Lake areas in central Alberta. The study was based on the examination, processing and interpretation of information from 6276 wells distributed over a total area of 39,500 km². The information processed refers to stratigraphic picks, chemistry of formation waters, drill stem tests and bottom hole temperatures. As a result, every stratigraphic unit is defined in terms of geometry and lithology, and characterized by appropriate hydraulic and thermal parameters. A sequence of eight major aquifer groups separated by eight aquitards and two aquicludes was identified. The fluid flow in the Paleozoic aquifers is mainly horizontal and regional in nature, being driven by the difference in hydraulic potential between the high areas in the foothills and the lowland areas in the prairies. The fluid flow in the Cretaceous aquifers is of regional to intermediate type, with a significant downward component. The fluid flow in the aquitards is vertical. The very low permeability of the strata is reflected in flow velocities on the order of magnitude of 1 cm/a and less. Dimensional analysis of heat transport processes in each hydrostratigraphic unit shows that convective heat transfer is negligible with respect to conductive heat transfer. The respective values of the Peclet number for heat flow in porous media areas are less than 10-2. In the Swan Hills and Cold Lakes areas the flow of the terrestrial heat flux from the crystalline Precambrian basement of the sedimentary basin to the atmosphere is controlled by the geometry and the changes in the thermal properties of the formations in the basin. The geothermal gradients for individual layers vary from 17 mK/m for sandstone units to 42 mK/m for shales. The integral geothermal gradient of the entire sedimentary column varies between 22 mK/m and 36 mK/m. The areal distribution of the integral geothermal gradient shows a strong correlation with stratigraphy and lithology.

Efficiency coefficient of water supply and removal as an assessment factor of further operation

During operation, pipeline hydraulic characteristics change due to the presence of sedimentary layers in pipes. The efficiency coefficient in an important parameter for the evaluation of the pipeline operation.Purpose: The aim of this work is to prove the necessity of using the efficiency coefficient in the hydraulic analysis of water supply and removal with internal sedimentary layers in pipes in order to predict their hydraulic characteristics with any (measured) thickness of the sedimentary layer.Methodology: Dependences used herein are repeatedly published by the authors.Research findings: Calculation tables are developed to design the reference manual "Calculation tables for hydraulic analysis of water removal in pipes with sedimentary layers".Practical implication: The proposed values of the efficiency coefficient of water supply and removal can be used in hydraulic calculations to predict the hydraulic potential of pipes with sedimentary layers.

Generation of Electricity From a Hydraulic Turbine in the Djonou River (Benin)

The shortage of electricity in rural areas despite the hydraulic potential they possess is becoming a challenge for Benin. To date, nearly 140,000 people spread over the 42 lakeside villages of this country live in energy inaccessibility, insecurity and poverty. To overcome this situation, the present study is therefore interested in the production of electrical energy on an experimental basis in low water periods thanks to an Archimedean screw turbine which operates at low flow rates and height of fall on the river. Djonou located in southern Benin a few kilometers from the University of Abomey-Calavi. The geometrical and hydraulic parameters of the screw were therefore determined and the device was modeled using Autocard software. A prototype was then made with local recycled materials and tested on the river. The screw specifications indicate an inside and outside radius of 0.072 m and 0.135 m. The length of the screw was set at 0.46 m for a blade radius estimated at 0.137 m. The number of screw blades is equal to 2 with a flow rate of 0.049 $ m^{3}/s $. The inclination angle of the screw is $25^{\circ}$. The device on the experimental site produces a voltage of 16 V and provides a current of about 0.12 A which can power a 2 W lamp. This performance of the prototype made on a small scale is a reliable indicator of the optimal use of this technology in the national hydraulic network of Benin to supply populations with electrical energy.

Optimization Studies on the Changeable Components of Hydroelectric Power Plants

The design flow rate, the dimensions of the transmission structure and the penstock size have a large impact on the cost of run-of-river type hydroelectric power plants. Equipment costs constitute a large part of the total budget of the plant. Optimum sizing, which maximizes the use of hydraulic potential, does not fit together with optimum sizing, which is necessary to obtain economic benefit from its investment. The main design parameters can be selected with the help of an optimization study in terms of both economic benefit and hydraulic potential. In this study, an easy to implement model, aimed at determining the costs associated with the different components in the structural organization of a hydroelectric power plant, is developed by a feasibility study to overcome the difficulties in practice. Gokcekoy HEPP, built in Turkey, was selected as the system. Annual energy production values were calculated by taking into account the current energy market conditions in Turkey. In addition, real situation studies were carried out regarding design flow rate selection, forced pipe diameter optimization and transmission channel sizing.

Basal Melt Patterns around the Deep Ice Core Drilling Site in the Dome A Region from Ice-Penetrating Radar Measurements

Basal melt in the Dome A region will influence the deep-ice-core drilling at Kunlun Station. The melting point (wet bedrock) has a higher reflectivity than the surrounding area, which can be assessed using radar echoes from the bedrock. This paper uses a linear absorption model to determine wet and dry ice–bedrock interfaces around the Kunlun drilling site. In the determination process, an artificial intelligence model was applied to extract the ice–bedrock interface for inferring the ice thickness. Additionally, the various depth-averaged attenuation rates were used to identify the maximal range of basal melting. We mapped the patterns of the wet points on the bottom of the ice sheet and the modeled basal temperature to verify the results of the wet bed conditions. According to these maps of wet bed conditions, the areas with basal melting around the drilling site primarily appear in valley walls with low basal temperatures and are linked with hydraulic potential and bedrock elevation. Identifying the ice–bedrock interface is challenging in the valley bottom area, where the melting points are less than at the valley walls. Additionally, the melting proportions of 11.8% and 3.62% were calculated from two ice-penetrating radar data in this research. The mapped melting points around the site of Kunlun ice core drilling suggest complex ice flow effects and can be used to better interpret archives of old ice for paleoclimate research.

State of the Art in Designing Fish-Friendly Turbines: Concepts and Performance Indicators

The expanding role of renewable energy sources in the electricity market share implies the increasing role of hydropower and the exploitation of unharnessed hydraulic potential, in the scope of sustainability and net zero emissions. Hydro-turbine design practices are expected to expand beyond achieving high efficiency goals, to multi-objective criteria ranging from efficient reversible operation to fish-friendly concepts. The present review paper outlines fundamental characteristics of hydropower, summarizing its potential impact toward aquatic life. Estimates of lethality for each damage mechanism are discussed, such as barotrauma, blunt impact and shearing, along with relevant advances in experimental techniques. Furthermore, numerical techniques are discussed, ranging from simple particle tracking to fully coupled six-degree-of-freedom tracking, which can be used to investigate candidate designs and their fish-friendly performance, presenting their advantages and disadvantages. Subsequently, a link to the individual damage mechanisms is established, to proposed holistic performance metrics, useful for providing estimates of fish-friendliness of a given hydropower installation. Finally, recent developments and design practices for fish-friendly turbine concepts are presented.

Mapping of Aquifer Potential in the Northeast Basement Rock of Burkina Faso: Using Remote Sensing and Geophysical Methods

The North-East of Burkina Faso is made up of formations of the Birimian basement rock. The region has a Sahelian climate where surface water resources are very limited. In order to assess the hydraulic potential of the existing aquifers, remote sensing and geophysical techniques (aeromagnetic and ground electric) were used. Satellite image processing and aeromagnetic survey data were used to generate a lineament map that was subsequently validated on the basis of existing geological, hydrogeological and topographical data, geomorphological field surveys and ground geophysical work. The resulting map displays a more or less dense network of 405 magnetic lineaments with a cumulative length of 1,787,676 meters as opposed to 94 lineaments from Landsat 8 images with a cumulative length of 970,054 meters. The average length of the magnetic lineaments is 4,414.01 meters while the average remote sensing length is 10,317.72 meters. The identified NE-SW and WNW-ESE fracture corridors are propitious for the presence of fracture aquifers. In addition to the lineament validation, the ground geophysics performed through electrical surveys allowed the characterization of the aquifers in the study area. Alteration thicknesses are generally less than 20 meters deep. The fractured horizon can reach 100 meters thickness under the alterites. The kernel density map highlights areas of good aquifer potential that could constitute significant groundwater reserves. Mapping aquifer potential is a crucial step in ensuring sustainable and efficient use of groundwater resources.

Dimensional Characterization of Groundwater Oblique Flow Problems with Heat Transport.

A dimensional study of two problems in which the groundwater flow is oblique has been carried out in order to characterize the vertical profiles of temperature along the domain affected by the flow, determining an input region in which the profiles depend on the horizontal position follow by a region in which profiles only depend on the vertical component of the flow. In the first problem, the horizontal and vertical components of velocity are constant. In the second scenario, the oblique flow of groundwater is generated because in the boundary conditions, the hydraulic potentials present a constant value. From the discriminated dimensional analysis of the mathematical model (governing equations and boundary conditions), the dependencies of the unknowns of greatest interest, characteristic lengths for the development of temperature-depth profiles and velocity profiles and the temperature field, with the dimensionless groups deduced are established. Once these dependencies have been verified, they are graphically represented by means of curves and surfaces as universal solutions to these problems. Based on these universal solutions an inverse problem protocol for estimating water flows from temperature measurements is proposed. The use of universal graphs of the two proposed scenarios avoids the large number of numerical simulations that this type of problem required.

Methodological approaches to assessing the efficiency of operation of gravity drainage networks with deposits in the tray part of pipes

Purpose: On the basis of methodological approaches to assessing the efficiency of operation of gravity drainage pipelines made of polymer materials with deposits in the tray part of pipes, to develop a sequence of hydraulic calculation of pipes with deposits and a methodology for evaluating the efficiency of their operation by the value of the hydraulic efficiency coefficient of the network.
 Methods: Based on the developed sequence of hydraulic calculation of drainage pipes made of polymer materials with deposits in their tray part, establish the procedure for calculating the values of the actual characteristics of the hydraulic potential of polymer pipes, which allows calculating for the example given the value of the coefficient of hydraulic efficiency of network operation, according to which a decision is made on the possibility of continuing its further operation.
 Results: Analysis of the values of the hydraulic characteristics of new pipes and polymer pipes with deposits in their tray part, for the example given, allowed us to establish significant discrepancies in their values. This made it possible to calculate the value of the hydraulic efficiency coefficient of the pipeline to make a decision on the possibility of continuing further operation.
 Conclusion: For the specific conditions of the task, a sequence of hydraulic calculation of pipes made of polymer materials with deposits in their tray part has been developed. It is proposed to conduct special studies on pipes made of different types of materials with deposits in their tray part to establish acceptable values of the thickness of the sediment layer in the tray part of the pipes for subsequent assessment of the possibility of their further operation.

ОБ АКТУАЛЬНОСТИ РАЗРАБОТКИ СПРАВОЧНЫХ ПОСОБИЙ ПО ГИДРАВЛИЧЕСКОМУ РАСЧЕТУ ИЗНОШЕННЫХ ИНЖЕНЕРНЫХ СЕТЕЙ ГОРОДСКОЙ ИНФРАСТРУКТУРЫ

When designing and reconstructing engineering networks of urban infrastructure, design organizations use a set of classical formulas for hydraulic calculation of pipelines. They don’t take into account changes in hydraulic potential during operation, and it leads to significant errors. This justifies the need to develop and refine reference manuals for hydraulic calculation of worn-out metal water supply, sewerage and heating networks of urban infrastructure. A specific example graphically demonstrates the influence of the thickness of the layer of internal deposits on the accuracy of the hydraulic calculation of pipes, i.e. on the determination of the parameters of their hydraulic potential. Based on the proposed methods of hydraulic calculation of pipes, we proved the relevance of revise the special reference manuals with taking into account actual changes in the values of hydraulic characteristics of metal pipelines in the process of their operation, in particular, the value of the coefficient of hydraulic efficiency of the pipeline.

A HYBRID FRACTIONAL-DERIVATIVE AND PERIDYNAMIC MODEL FOR WATER TRANSPORT IN UNSATURATED POROUS MEDIA

Richards’ equation is a classical differential equation describing water transport in unsaturated porous media, in which the moisture content and the soil matrix depend on the spatial derivative of hydraulic conductivity and hydraulic potential. This paper proposes a nonlocal model and the peridynamic formulation replace the temporal and spatial derivative terms. Peridynamic formulation utilizes a spatial integration to describe the path-dependency, so the fast diffusion process of water transport in unsaturated porous media can be captured, while the Caputo derivative accurately describes the sub-diffusion phenomenon caused by the fractal nature of heterogeneous media. A one-dimensional water transport problem with a constant permeability coefficient is first addressed. Convergence studies on the nonlocal parameters are carried out. The excellent agreement between the numerical and analytical solutions validates the proposed model for its accuracy and parameter stability. Subsequently, the wetting process in two porous building materials is simulated. The comparison of the numerical results with experimental observations further demonstrates the capability of the proposed model in describing water transport phenomena in unsaturated porous media.