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Earthworms and plant roots are vital for macropore formation and stabilization. The organo‐mineral coating of biopore surfaces also regulates macropore‐matrix mass exchange during preferential flow. The influence of finer‐textured burrow coatings on macroscopic soil properties during shrinkage could potentially be assessed by upscaling pore‐scale hydraulic and mechanical simulations. The aim was to investigate the influence of micro parameters (particle size, stiffness, and bond strength) on macro parameters (i.e., shrinkage curve and soil hydraulic properties). Drainage experiments and simulations were carried out using biopore‐coated clod‐size samples compared to those without coating. Simulations were performed using a two‐phase pore‐scale finite volume coupled with discrete element model (DEM‐2PFV). The structural dynamics was characterized by analyzing the pore volume and soil shrinkage curve obtained from numerically determined data. The soil hydraulic parameters were described using uni‐ and bimodal van Genuchten (vG) functions. The drainage simulations revealed hydro‐mechanical dynamics characterized by Braudeau‐shrinkage curve subdomains: The matrix‐only samples, with lower particle bond strength, exhibited relatively higher shrinkage. The coated samples, with higher particle stiffness and bond strength, displayed greater hydro‐mechanical stability. The numerically determined initial value of the saturated hydraulic conductivity (Ks) was about 70 times larger for matrix‐only samples than for coated samples. As expected, for the nonrigid soil structures, constant Ks, α, and n values for bimodal vG model resulted in prediction errors. Upscaling DEM‐2PFV pore‐scale model outcomes quantifies micro‐coating effects on macro hydro‐mechanics. This yields void ratio‐based soil water retention and hydraulic conductivity functions, advancing macroscopic soil hydraulic models and enhancing structured soil flow and transport descriptions. Core Ideas: Constant hydraulic properties led to prediction errors in nonrigid soil structures.Upscaling pore‐scale simulations quantified shrinkage and water retention curves.Coated biopore surfaces increase soil horizontal hydro‐structural stability. [ABSTRACT FROM AUTHOR]

This paper presents an extensive study on the electrochemical, shunt currents, and hydraulic modeling of a vanadium redox flow battery of m stacks and n cells per stack. The shunt currents model of the battery has been developed through the use of Kirchoff's laws, taking into account the different design cases that can occur and enumerating the equations of nodes and meshes specifying them so that the software implementation can be performed in a direct way. The hydraulic model has been developed by numerical methods. These models are put to work simultaneously in order to simulate the behavior of a VRFB battery during charging and discharging, obtaining the pressure losses and shunt currents that occur in the battery. Using these models, and by using a PSO-type optimization algorithm, specifically designed for discrete variables, the battery design is optimized in order to minimize the round-trip efficiency losses due to pressure losses and shunt currents. In the optimization of the battery design, value is given to the number of stacks in which the total number of cells in the battery is distributed and the dimensions of the piping relative to both the stacks and the cells. [ABSTRACT FROM AUTHOR]

Water distribution network (WDN) models are a common decision support tool for understanding the behavior and performance of WDNs, aiding in the planning and management of WDN systems. The increasing availability of real-time data has recently promoted the exploration of Data Assimilation (DA) techniques to improve these models. However, flow, pressure and demand data are uncertain, particularly due to sensor characteristics such as precision and noise. An open question is to what extent DA can still improve hydraulic models when the data used to this end is uncertain. This paper proposes a three-step Ensemble Kalman Filter based DA approach for WDNs (3-EnKF-WDN), building on previous approaches, and advancing in two main fronts: the use of extended period simulation, and the use of pressure-dependent demand (PDD) analysis. Different scenarios considering uncertain sensor data, with varied precision and noise, are applied to two networks of different sizes, representative of real-world WDNs. The computational demand of the 3-EnKF-WDN method is also assessed. Results show that increasing sensor's precision and decreasing the noise in state measurements reduce model error, as expected. However, we also found that model errors: 1) are reduced more effectively by using 3-EnKF-WDN than by increasing sensors' precision; 2) are not reduced if certain noise thresholds are surpassed; 3) can be reduced without assimilating demand data if the WDNs are fully monitored with head sensors in all the nodes and flow sensors in all the links. [ABSTRACT FROM AUTHOR]

This study examines the spatial pattern of fractional sediment mobility and assesses the influence of morphologic units on bedload transport in a small pool‐riffle reach with limited supply. Using a 2D hydraulic model and a subsurface‐based sediment transport model, shear stresses, fractional sediment mobility, and bedload transport were examined for flow events ranging in magnitude between 0.2Qbf and 1.5Qbf. Results reveal that while spatial variations in shear stress decrease as discharge increases, only a small proportion of the bed experiences high transport rates. At the reach scale, riffles are the primary morphological unit contributing to fully mobile sediment for all size fractions. However, at a subunit scale, there is evidence of sediment transport reversal for grains >32 mm at flows near or exceeding bankfull discharge in association with shear stress reversal. These transport reversals are important for maintaining pools despite their infrequent occurrence in the study reach. Sediment transport maps indicate that bed morphology considerably influences sediment transport at low to moderate flows. During these events, the shear stress is sensitive to local bed topography and partial mobility is the dominant transport process. In contrast, variations in bedload transport rates decrease during high flows when the flow is less sensitive to variations in bed topography and the bed becomes fully mobile. Key Points: A scaled version of a subsurface‐based model was utilized to evaluate the impact of morphologic units on fractional sediment mobilityRiffles were found to be the main source of fully mobile sediment of all sizes, with local transport reversal observed for grains >32 mmThe impact of morphologic units on bedload transport is more pronounced during low and moderate flows and diminishes during high flows [ABSTRACT FROM AUTHOR]

The constitutive relations of the Richardson‐Richards equation encode the macroscopic properties of soil water retention and conductivity. These soil hydraulic functions are commonly represented by models with a handful of parameters. The limited degrees of freedom of such soil hydraulic models constrain our ability to extract soil hydraulic properties from soil moisture data via inverse modeling. We present a new free‐form approach to learning the constitutive relations using physically constrained neural networks. We implemented the inverse modeling framework in a differentiable modeling framework, JAX, to ensure scalability and extensibility. For efficient gradient computations, we implemented implicit differentiation through a nonlinear solver for the Richardson‐Richards equation. We tested the framework against synthetic noisy data and demonstrated its robustness against varying magnitudes of noise and degrees of freedom of the neural networks. We applied the framework to soil moisture data from an upward infiltration experiment and demonstrated that the neural network‐based approach was better fitted to the experimental data than a parametric model and that the framework can learn the constitutive relations. Key Points: We developed a fully‐differentiable solver for the Richardson‐Richards equationThe constitutive relations are represented by physically constrained neural networksThe framework can be used to extract soil hydraulic properties without assuming coupling between the constitutive relations [ABSTRACT FROM AUTHOR]

In order to predict groundwater pressure on tunnel linings with embedded drainage networks, as needed in the design of tunnels under high water pressure, a coupled hydraulic model is proposed by incorporating seepage in the surrounding rocks and pressurized flow in the networks. The model is executed using the software Comsol Multiphysics and applied to analyses of a high-speed railway tunnel in China. Comparative analyses indicate that the model is more comprehensive and accurate than existing models in the literature. For rocks with low hydraulic conductivities (< 3 × 10−5 m/s), the water pressures calculated from the existing models are about the same as those from the proposed model; however, for rocks with medium to high hydraulic conductivities (> 3 × 10–5 m/s), the existing models may err on the unsafe side by significantly underestimate the water pressures. Moreover, the more permeable the rock, the greater the underestimation of the water pressure on the lining. Meanwhile, some valuable suggestions for the embedded drainage networks are obtained through parametric analysis based on the proposed model. The proposed model is valuable for designing linings with embedded drainage networks for tunnels under high water pressure. [ABSTRACT FROM AUTHOR]

The long-distance multi-stage pressurized pump station water delivery system involves numerous valve closure parameters, complicating the rapid identification of an optimal valve closure scheme that satisfies multiple transient flow oscillation protection requirements. A hydraulic transient model was established based on transient flow calculation theory to address this challenge. Decision biases were identified using the Analytic Hierarchy Process and the Entropy Weight Method. A multi-objective optimization model, incorporating Support Vector Regression (SVR) and the Beluga Whale Optimization (BWO) algorithm, iteratively searches for optimal schemes under different biases. The results indicate that Support Vector Regression exhibits optimal performance, while Beluga Whale Optimization demonstrates excellent performance. The optimal schemes obtained from the multi-objective optimization model meet the transient flow protection requirements of the water delivery system. The study demonstrates that this model effectively solves the multi-objective optimization problem for water hammer protection in multi-stage pressurized pump station water delivery systems. [ABSTRACT FROM AUTHOR]

Cities with sloping terrain are more susceptible to flooding during heavy rains. Traditional hydraulic models struggle to meet computational demands when addressing such emergencies. This study presented an integration of the one-dimensional Storm Water Management Model (SWMM) and the two-dimensional LISFLOOD-FP model, where the head difference at coupled manholes between the two models functioned as the connection. Based on its calculation results, this study extracted the characteristic parameters of the rainfall data, simplified the SVR calculation method and developed a high-efficiency solution for determining the maximum ponding depth. The cost time of this model was stable at approximately 1.0 min, 95% faster compared to the one from the mechanism model for 5 h simulation under the same working conditions. By conducting this case study in Jiujiang, China, the feasibility of this algorithm was well demonstrated. [ABSTRACT FROM AUTHOR]

This article uses on-site drilling data and establishes a hydraulic model for pressure-controlled cementing to simulate and analyze the generation process of the vacuum interval in the wellbore, as well as the changes in the volume and height of the vacuum interval, bottom hole pressure, and point of interest pressure over time. This model can optimize and recommend key parameters such as target wellhead back pressure and displacement based on the pressure window and drilling parameters, with the target pressure of the focus point as the anchor point. Through the hydraulic model of controlled pressure cementing, the hydraulic parameters and processes of managed pressure cementing can be optimized and recommended, effectively ensuring the safety of the cementing process. [ABSTRACT FROM AUTHOR]

For the shaft sealing of a repository for radioactive waste, a Sandwich sealing system was developed by KIT-CMM consisting of bentonite-based sealing segments (DS) and sand mixture-based equipotential segments (ES). To demonstrate the functionality of the Sandwich sealing system, various laboratory tests (MiniSandwich tests and semi-technical scale experiments) have been carried out before a large-scale experiment has been implemented in situ at the Mont Terri Rock Laboratory (CH). An important coupled process in the Sandwich system is the swelling deformation of the DS while aqueous fluid penetrates into the system. Consequently, the interparticle porosity (effective porosity) of the DS decreases by swelling strain, resulting in a reduction in the permeability of the DS. Pore space of the ES also decreases slightly due to swelling stress in the adjacent DS, which also leads to a reduction in the permeability of the ES. To understand the coupled hydromechanical processes of the Sandwich sealing system, a numerical model was developed to interpret the experimental observations from the MiniSandwich tests and to parameterize different components. A linear swelling model for DS and empirical functions for the swelling deformation-induced permeability change for both DS and ES segments were introduced into the coupled model with Richards' flow and elastic model. Sensitivity analysis with parameter variations of the most important parameters reduces the uncertainty in the system behavior. Highlights: The Sandwich concept is an innovative idea for realizing the sealing effect in a repository for radioactive waste. The MiniSandwich experiments are carried out under well-defined conditions and reveal the hydromechanical responses in the Sandwich system and provide a high-quality database. A simple emperical model based on physical observations was developed to simulate the measured flow and stress and to account for the interaction between sealing segment (DS) and equipotential segment (ES). In this model, swelling-induced permeability change for DS and compaction-induced permeability change for ES are intensively studied. [ABSTRACT FROM AUTHOR]

Most models employed for fluid forces in drill-string dynamics are of reduced order. The simplified nature of these models often fails to describe the complex behavior of the fluid force, in particular, when the drill-string movement is non-trivial or even when non-Newtonian behavior is predominant. In this work, the fluid forces are estimated by modeling the dynamic of the drilling fluid for both Newtonian and non-Newtonian fluids, and compared with reduced-order models. To achieve it, the lattice-Boltzmann method is implemented to solve the fluid model, while prescribed movements are set for the tool-joint. With the obtained fields, the forces are calculated and compared with recurrent models. Finally, it is observed that some models are capable of describing the interaction as long as the dynamic of the tool-joint is simple. In the presence of other trajectories--e.g., bouncing and chaotic--the models fail to describe the details of the dynamic. [ABSTRACT FROM AUTHOR]

The fluid–solid coupling effect is more pronounced in the process of deep coal seam development compared to shallow coalbed methane, exerting a greater influence on production, and cannot be disregarded. Throughout the extraction process, the interaction between effective stress and gas desorption triggers deformation within the coal seam, leading to dynamic changes in both porosity and permeability. This paper has developed a fully coupled gas flow and deformation model that contains the coal matrix and discrete fractures to describe the dynamic gas seepage behavior and deformation of deep coal seams within a coupled wellbore–hydraulic fractures–matrix system. The model's validity is corroborated through the examination of fracture aperture, employing the finite element numerical simulation capabilities of COMSOL Multiphysics. Subsequent to the model's validation, an in-depth investigation into the permeability and production variations under diverse parametric conditions is conducted. This analysis also encompasses the assessment of hydraulic fracture geometry's impact. The simulation outcomes reveal that the permeability alterations during coal seam development are subject to the counteracting influences of gas desorption and effective stress. Moreover, it is observed that an increase in the Langmuir volume strain constant and initial porosity correlates with enhanced production, whereas a diminution in the hydraulic fracture compression coefficient leads to increased cumulative production. Notably, the optimal production is attained when hydraulic fractures are oriented vertically yet asymmetrically relative to the horizontal well. [ABSTRACT FROM AUTHOR]

This paper analyses flood frequency and performs flood simulation modeling along the Chenab River from Trimmu–Panjnad reach, to simulate flood 2014 and identify resultant flood inundated areas, under different return periods of floods. The aim of this study is to assist policymakers in designing efficient flood mitigation policies for the Chenab River, Pakistan which has been frequently hit by floods, especially in September 2014. Flood frequency analysis was carried out using log-Pearson type III (LP3) distributions to estimate peak flows with various return periods. The peak floods were incorporated into the Hydrologic Engineering Centre River Analysis System (HEC-RAS) model to predict the relevant flood levels for river stretches from Trimmu to Panjnad reach. The HEC-RAS model outcomes were integrated with ArcGIS to prepare flood risk maps that helped in identifying different flood-vulnerable areas. Two flood risk zones were developed; low to moderate and high to very high flood risk zones. The simulation analysis of a 50-year flood period showed that about 400% of the land would be submerged when compared to normal river flow. The simulation of the flood 2014 extent was found to clearly match the MODIS images provided by the United Nations Satellite Centre (UNOSAT). The surface areas of floods having different return periods, were also estimated. The utilization of the HEC-RAS model for simulating the 2014 flood, presents an opportunity for flood policymakers to enhance their understanding and formulate effective risk reduction strategies in the Chenab River basin. [ABSTRACT FROM AUTHOR]

Flooding carries risks on life, property and infrastructure posing a need for efficient management and mitigation strategies. The project's main focus is on flood analysis of Mula-Mutha River in Pune, India and it involves the use of Hydrologic engineering center's river analysis system (Hec-Ras). The main goal is to model floods, determine areas prone to flooding and suggest how to prevent such through comprehensive hydraulic modeling. In this research, we collect topographic and hydrological data due to including river geometry, flow rates and rainfall patterns. by using those data inputs, a detailed Hec-Ras model of the Mula-Mutha river is created. Various flood events are simulated by the model to analyze water surface profiles, flow velocities, and floodplain extents under different conditions. Important findings show that several regions are at high risk of being flooded because of their riverbank geometry, urban development progress or how hard rain falls. Historical flood records together with exercises that checked for truth and accuracy were involved in validating the results gotten. From the examination the study suggests both structural and non-structural flooding prevention measures like making levees, building floodwalls and setting in place better urban drainage systems. Importance of advanced hydraulic modeling tools like Hec-Ras in flood risk management and urban planning is what this study is looking into. Mula-Mutha River basin will use this research project to provide reliable flood predictions and help local authorities improve flood preparedness and resilience through identification of high-risk locations. [ABSTRACT FROM AUTHOR]

In the 1D–2D coupled simulation of urban waterlogging, the calculation process of vertical flow exchange is independent from the 1D hydraulic calculation, resulting in a failure to consider the node head and pipe flow during the exchange flow calculation, which may lead to irrational results and further affect the stability of the model calculation. However, setting an upper limit for the exchange flow may introduce excessive subjective factors into the simulation process. In this study, a vertical flow exchange method based on the water balance of nodes is proposed. When a node is in an overloaded state, the calculation of vertical flow exchange at the node is integrated into the 1D hydraulic simulation process, thus taking into consideration the influence of the node head and pipe flow when calculating vertical flow exchange. Additionally, the iterative solution method used in the 1D hydraulic model ensures numerical harmony between the vertical flow exchange, node head and pipe flow, thus ensuring the stability of the coupled calculation. For the non-overloaded nodes, the calculation of the vertical flow exchange was conducted using a variable-head orifice discharge formula, enabling the consideration of changes in the surface water depth during the calculation of the node backflow. Using the InfoWorks ICM model as a benchmark, a comparative analysis of case simulation results demonstrated that the improved vertical flow exchange method was able to accurately and stably simulate the process of vertical flow exchange. When used with the improved vertical exchange method, the coupled model gave simulation results that closely matched those of the benchmark model. [ABSTRACT FROM AUTHOR]

Ground vibration induced by high dam flood discharge has been reported to cause severe structure safety threats and environmental issues. In this paper, an evaluation and reduction approach for ground vibration using systematic and comprehensive studies is proposed. Based on the results of hydraulic physical model tests, the hydrodynamic excitation on the stilling basin plate (SBP) is analytically expressed as spatially variable harmonic loads by the three-dimensional least squares method. Afterwards, a theoretical model for the SBP–foundation coupled system is established and the vibration of SBP subjected to analytical hydrodynamic load input is calculated. The ground vibration is further evaluated through the numerical simulation regarding the SBP vibration as the input load. According to the prototype test result, it is found that the variation trend of evaluation results under different working conditions is consistent with the actual situation, which indicates the effectiveness of this evaluation approach. Furthermore, the sensitivity analysis of SBP physical dimensions to ground vibration is conducted, and an optimized design for SBP is presented as a result. The verification results indicate that ground vibration can be significantly reduced by applying SBP optimization. [ABSTRACT FROM AUTHOR]

In order to improve the hydraulic efficiency and internal flow pattern of a multi-stage pump under multiple flow conditions, an intelligent optimization design was proposed for its hydraulic components. Sensitivity analysis was used to select the key parameters influencing the hydraulic efficiency of a multi-stage pump. The optimal Latin hypercube sampling and non-dominated sorting genetic algorithm Ⅱ were employed to build a multi-objective optimization system. Moreover, a radial basis function neural network was adopted as the surrogate model of hydraulic efficiency. The research results showed that the impeller outlet width, impeller blade wrap angle, impeller outlet blade angle, and diffuser inlet width were the key factors affecting the hydraulic efficiency. The efficiency of the optimized model increased by 4.35% under the design condition and the matching of the internal flow between the optimized impeller and diffuser was significantly enhanced under the nominal condition. The improved flow pattern could be clearly observed in the flow passage of both the pump impeller and the diffuser. After optimization, the wear performance of the model was also improved compared to the original design. The wear area decreased in size and was distributed more evenly, resulting in a noticeable decrease in the maximum amount of wear. [ABSTRACT FROM AUTHOR]

Sectorization of a water distribution network (WDN) into district meter areas (DMAs) is considered a key strategy for an efficient management of WDNs. Typically, it involves a two-stage procedure: a clustering stage, in which the division of the WDN into clusters is performed, and a dividing stage, which involves the placement of valves and flow meters on the cluster's boundary pipes to define the DMAs. While recently published methods attempt to enhance both the clustering and dividing stages, they fail to provide decision-making flexibility. They also neglect to consider the presence of existing valves in the WDN, which can significantly affect the evaluated implementation cost, often considered the primary decision-driving factor. This paper presents improvements to the previously introduced DeNSE method for sectorization of WDNs, aiming to address these deficiencies. The methodology consists of a clustering stage, based on the network uniformity index, and a dividing stage, in which the originally used heuristic procedure is replaced with Genetic Algorithm (GA) optimization, minimizing implementation cost. Consideration of existing valves in WDN and criteria for water supply security are also included in the dividing stage to offer a better estimate of implementation costs and post-sectorized operational efficiency of the WDN. Finally, GIS visualization is implemented, and a hydraulic model of the sectorized WDN (EPANET file) is generated, providing practitioners with valuable insights and decision-making flexibility. The methodology is tested on a part of the Amsterdam WDN in the Netherlands, serving as a pilot for methodology evaluation. A range of feasible sectorization solutions is generated and compared based on implementation cost and three performance indicators (PIs). The paper provides an in-depth discussion on the selection of preferable sectorization solution. The reported results demonstrate the method's efficiency in optimizing sectorization solutions with minimum implementation cost whilst preserving the WDN operational efficiency and meeting the local design criteria. [ABSTRACT FROM AUTHOR]

This article highlights some methods for determining the optimal accumulator for the hydraulic units with accumulators used in the locking and clamping/unclamping systems for machine-tools. The mathematical models and the results of the simulations carried out for designing such units are shown below. The results of the research can also be applied in the case of the clamping/unclamping systems for the toolholders of the machine-tools or similar systems. [ABSTRACT FROM AUTHOR]

The paper presents an overview of the efficiency for a hydraulic circuit with 4/2-way hand-lever valves. Thereby in this article we are studying three hydraulic circuits which contain 4/2-way hand-lever valves. The first hydraulic circuit contains the following devices: pump unit, tank, 4/2-way hand-lever valve, throttle valve, double acting cylinder (Dou 1-1). The second hydraulic circuit contains the following components: pump unit, tank, 4/2-way hand-lever valve, pressure relief valve, double acting cylinder (Dou 2- 1), and 2-way flow control valve. The last circuit, which is actually a hydraulic system, contains the following components: pump unit, tank, 4/2-way hand-lever valve, non-return valves, 2-way flow control valve, double acting cylinders (Dou 3-1 and Dou 3-2). [ABSTRACT FROM AUTHOR]

Ecosystem management depends on transforming qualitative observations (e.g., slow‐moving shallow conditions provide nursery refugia for silvery minnow larvae) into management actions to increase habitat quantity or improve habitat quality. To be effective, decision metrics that are developed for management objectives should be validated with field observations. Model assumptions, precision and parameter importance can be refined by comparing the fidelity of selected parameters computed as habitat quality metrics and the correlation of these metrics to real‐world observations. Validated environmental metrics are more credible for management and can be compatible with ecosystem monitoring and project design processes. In this study, streamflow monitoring data and hydraulic modelling are used to quantify fish habitat extent for 15 years of spring runoff. The spring runoff event coincides with larval maturation to a free‐swimming juvenile phase for the silvery minnow, a critical period in Rio Grande habitat management. Different methods to estimate habitat availability (i.e., hydrology statistics, inundation extents based on hydraulic modelling and areal habitat availability based on different formulations of a habitat suitability index curve) were used to test the efficacy of different metrics relative to species population monitoring. This analysis finds that flow–ecology relationships based on hydraulic modelling or hydrology statistics are both effective and highly correlated to larval production. The investigation shows how seasonal hydrologic characterization and hydraulic discretization have varying levels of correlation with seasonal fish production. This study demonstrates how hydraulic modelling data and hydrologic characterization of riverine environments can be used to validate or develop conceptual ecological models. [ABSTRACT FROM AUTHOR]

The determination of minimum flow requirements for green small hydropower plants (GSHP) in China primarily relies on hydrological methods such as the Tennant method with no seasonal variation. However, the direct application of hydrological methods without local ecological data for calibration lacks ecological validity, potentially resulting in unsuitable minimum flow recommendations for local aquatic biota. Hydraulic‐habitat modelling (HHM) is assumed to provide more ecologically relevant and reliable environmental flow recommendations (EFRs), but benthic macroinvertebrates (BMs), crucial in the aquatic food web, have rarely been the focus in HHM studies. Moreover, the strong subjectivity in HHM processes hinders the comparison of EFRs across different biota and geographical regions. This study aims to investigate the ecological validity of using the Tennant method to set minimum flow requirements for local BM communities and the impacts of various methods used in HHM on derived EFRs. To achieve this, a pseudo‐2D HHM approach is employed, integrating the 1D hydraulic models HEC‐RAS and CASiMiR with the habitat model HABFUZZ. The EFRs downstream of Jiufeng reservoir, one of China's first GSHPs, are derived for wet (April–June) and dry seasons (July–September). Our findings highlight that setting minimum flow alone is inadequate for preserving BM community integrity downstream of GSHPs. It is crucial to incorporate more diverse environmental flow criteria, including minimum flows and peak flows, into GSHP assessment standards, with recommended flow levels varying across different seasons. Additionally, the development of a standardized HHM methodology is essential to mitigate the inherent subjectivity in HHM and facilitate the comparison of EFRs generated from different studies. This study's innovative modelling framework and findings will enhance the optimization of minimum flow assessment criteria for GSHP in China, deepen understanding of seasonal e‐flow requirements of BM communities, and refine the methodology used in BM HHM for e‐flow recommendation. [ABSTRACT FROM AUTHOR]

Scour depth downstream of weirs is considered one of the most important hydraulic problems, which greatly influences the stability of weirs. Recently, artificial intelligence (AI) methods have become increasingly popular in modeling hydraulic variables, especially scour depth, because they can capture nonlinear relationships between input variables and their associated objectives. Despite their importance, these models have problems with hyperparameter tuning in scour depth modeling due to their structures, so algorithms must be used to tune the hyperparameters. Moreover, these algorithms are usually tuned by using the trial-and-error method to select the hyperparameters such as the number of hidden nodes, transfer function, and learning rate, and in this case, the main problem is overfitting during the training phase. To solve these problems, the high-order response surface method (HORSM), an improved version of the response surface method (RSM), is used as an alternative approach for the first time in this study to predict the scour depth. The HORSM model is based on high-order polynomial functions (from two to six) compared with the artificial neural network model (ANN). The findings indicate that the fifth order of the HORSM polynomial function yields the most precise predictions, with a higher coefficient of determination (R2) of 0.912 and Willmott Index (WI) of 0.972 compared to the values obtained using ANN (R2 = 0.886 and WI = 0.927). Moreover, the accuracy of the predictions is represented by a reduction of the mean square error by up to 44.17 and 29.01% compared to the classical RSM and ANN, respectively. The suggested model established an excellent correlation and accuracy with experimental values. [ABSTRACT FROM AUTHOR]

In this study, we propose a new approach for inverse modeling of hydraulic tomography (HT) using the Fourier neural operator (FNO) as a surrogate forward model. FNO is a deep learning model that directly parameterizes the integral kernel in Fourier space to learn solution operators for parametric partial differential equations (PDEs). We trained a highly accurate FNO to learn the solution operators of PDEs in HT, which can efficiently generate multiple channels of hydraulic head fields corresponding to specific pumping tests in new parameter fields through a single forward pass. The trained FNO surrogate model is integrated with the reduced geostatistical approach (RGA) to provide a powerful tool, named RGA‐FNO, for inverse modeling of Gaussian random fields. RGA utilizes principal components to effectively reduce problem dimensions and encode geostatistical information. FNO benefits from deep learning automatic differentiation, enabling efficient backpropagation of gradients during inverse modeling. Our results show that RGA‐FNO can efficiently produce satisfactory estimations for random transmissivity fields with an exponential covariance function, which is non‐differentiable and visually non‐smooth. The RGA‐FNO application on steady‐state multi‐well HT is better than the single‐well transient pumping test for inverse modeling. The data required for inverse modeling applications of RGA‐FNO increases with the variance of the random transmissivity fields. FNO and other neural operator models have the potential to play an important role in groundwater modeling, especially in inverse modeling and experimental design, which often requires a large number of forward simulations. Key Points: RGA‐FNO integrates the reduced geostatistical approach (RGA) with a Fourier neural operator (FNO) surrogate modelA highly accurate FNO was trained to learn the solution operators of PDEs in hydraulic tomography, generating multiple hydraulic head dataRGA‐FNO can efficiently produce satisfactory estimations for random transmissivity fields with high‐rank, small‐scale heterogeneities [ABSTRACT FROM AUTHOR]

Forecasting flood and drought events requires accurate modeling tools. Hydraulic river models are based on estimates of riverbed geometry which are traditionally collected in situ. The novel Ice, Cloud and Land Elevation Satellite 2 [ICESat‐2] lidar altimetry mission with 6 simultaneous high‐resolution laser beams provides the opportunity to define river cross‐section geometries as well as observe water surface elevation [WSE] and water surface slope spatially resolved along the river chainage. This paper describes a method to utilize terrain altimetry and water surface slope estimates to define complete river geometries from ICESat‐2 data products, using the diffusive wave approximation to calculate depth in the submerged section not penetrated by the lidar. Exemplifying the method, cross‐sections are defined for a stretch of the Mekong River. Hydrodynamic model results of the stretch are compared with ICESat‐2 WSE estimates and in situ gauging station time series. Insights in river characteristics from satellite imagery and the ICESat‐2 slope estimates allow for fine‐tuning of the cross‐sections using spatially varying Manning numbers. The final model achieves a root mean square error against the ICESat‐2 WSE of 0.676 m and average Kling‐Gupta Efficiency against gauging station time series of 0.880. The method is limited by the diffusive wave approximation resulting in inaccurate cross‐section estimates in sections with supercritical flow or significant acceleration. Errors can be identified from ICESat‐2 WSE estimates and reduced with additional cross‐sections. Combined with hydrological models, the method will allow for cross‐section definition without in situ data. Plain Language Summary: The depth and width of the river channel are important factors when seeking to predict floods. To predict water level in a river, computer models for flood forecasting must be informed with river channel geometry at cross‐sections along the river. Such cross‐sections are traditionally measured in the field which is expensive and time consuming. This paper describes a method to estimate river cross‐sectional shape from land and water height measurements from the satellite ICESat‐2. When the satellite path crosses the river, the precise laser instrument onboard outlines the surface to indicate the river channel shape, but it does not penetrate the water. We found that it was possible to estimate the shape of the submerged part of the cross‐section using the water surface slope obtained from the satellite's unique instrument. Evaluating the method on a stretch of the Mekong River, we were able to model water level along the river with accuracy sufficient for flood forecasting. In some sections, where the flow speed changes quickly, a hydraulic model with the defined cross‐sections does not reproduce observed water levels. Using satellite crossings from days with steadier flow reduces the error. The method allows for building hydraulic river models without cross‐section surveys. Key Points: Land elevation and water surface slope estimates from the ICESat‐2 lidar altimetry mission are combined to define river cross‐sectionsRMSE of 0.676 m and KGE of 0.88 is achieved for a hydrodynamic model of a stretch of the Mekong River using the derived cross‐sectionsSections with significant flow acceleration lead to inaccurate cross‐sections, but errors are reduced with additional ICESat‐2 crossings [ABSTRACT FROM AUTHOR]

The article discusses the importance of model calibration in water distribution systems. Hydraulic models are essential for planning, designing, and operating water systems, and model calibration helps build confidence in the results. The article highlights various issues that can affect model accuracy, such as simplifications, approximations, assumptions, and errors. The American Water Works Association (AWWA) has developed a comprehensive handbook for water distribution system model calibration, which provides a logical approach to the calibration process. The handbook covers topics such as measuring field data, identifying potential error sources, and making necessary adjustments. The article emphasizes the need for ongoing calibration as water systems are dynamic and constantly changing. Effective communication between modelers, system operators, and decision-makers is crucial for successful calibration. The benefits of calibration extend beyond the model itself, as it can help identify and resolve issues in the water utility. The AWWA handbook simplifies the calibration process and aims to create a useful hydraulic model that can support decision-making with confidence. [Extracted from the article]

The article presents an advanced two-dimensional (2D) computational fluid dynamics (CFD) model of an external gear pump which considers relief grooves. Relief grooves are limiting design features for the flow process of this type of pump, and their influence in existing studies is considered by a three-dimensional (3D) model only. The structural modification proposed by the authors is beyond the possibilities of real implementation, but it gives the possibility to precisely model the pump's design features. In contrast to the existing studies (using 3D CFD), the proposed advanced 2D model requires significantly fewer computing resources. Numerical experiments were carried out using the 2D model at different pump operating modes depending on the rotation frequency (950–1450 min−1) and pressure load (5–150 bar). The numerical results were validated by a real-world experiment for the same pump operating modes using an existing laboratory experimental setup. An analysis of the CFD model and real experiment results was carried out by determining a quantitative index of match (FIT), which varies in the range of 97.93–99.82%. This proves the performance of the proposed CFD model, which can be further used as a part of more complex hydraulic systems models. [ABSTRACT FROM AUTHOR]

With a focus on a specific flood-prone community in Camden, NJ, this research utilizes a detailed hydraulic and hydrologic (H&H) model to assesses the impacts of climate change on Combined Sewer Overflows (CSOs) and localized flooding under two different infrastructure scenarios. In the US, the Clean Water Act compels regulated utilities to develop Long-Term Control Plans to reduce combined sewer overflows (CSOs), but there is no parallel mandate to simultaneously reduce flooding within the associated service areas. With different control measures in place, H&H models are frequently used to evaluate CSO volumes and frequencies under historical climate conditions. However, precipitation intensification and sea level rise (SLR) will also modify CSO volumes. This study uses a calibrated and validated 1D and 2D Personal Computer Stormwater Management Model (PCSWMM) simulation to predict both CSO discharges and flooding under different climate and infrastructure scenarios. A total of ten climate change scenarios comprising a range of plausible climate futures are considered. The infrastructure scenario that is tested would divert stormwater generated in an upstream municipality (Pennsauken, NJ) away from Camden's combined sewer system. Without the disconnection, increases in precipitation will increase CSOs, whereas SLR primarily increases flooding. The proposed mitigation strategy can immediately reduce both CSOs and flooding, but with diminishing effectiveness over time, as climate change demonstrates the need for supplemental measures. Areas for further analysis regarding alternative mitigation methods and future research are outlined. [ABSTRACT FROM AUTHOR]

The existing hydraulic support attitude monitoring and control methods integrate multiple sensing technologies, but it is difficult to apply and promote due to unclear monitoring mechanisms, complicated types, and a large number of sensors. Aiming at the problem of attitude monitoring and control of hydraulic support, firstly, the kinematics mathematical model of hydraulic support is established by the key marker point method and the two-dimensional bar system model, and the forward and inverse solution algorithm of hydraulic support attitude based on the double-drive length of front and rear columns is proposed. Secondly, the rigid body dynamics simulation model of hydraulic support is constructed to verify the theoretical analytical model and prove the correctness of the algorithm. The rigid body simulation model can be used as the attitude monitoring system of hydraulic support. Thirdly, considering the influence of material elastic deformation, a rigid-flexible coupling dynamic simulation model of hydraulic support is established to explore the influence of elastic deformation of components on the attitude of hydraulic support and its causes. On this basis, the rigid-flexible coupling dynamic simulation model of the hydraulic support with clearance is established by replacing the revolute pair in the simulation model with the solid axis pin connection unit. The influence of the axis pin connection clearance on the attitude of the hydraulic support and its causes are explored, and the actual attitude and change characteristics of the hydraulic support under simulated real conditions are obtained. Finally, considering the force compression of the hydraulic cylinder of the column, the rigid-flexible and machine-liquid coupling dynamic simulation model of the hydraulic support with clearance is constructed. The loading test proves that the force compression of the hydraulic cylinder has a great influence on the attitude of the hydraulic support, indicating that when adjusting the attitude of the hydraulic support, the theoretical flow calculation cannot be used, and the column length should be directly measured. In this paper, the analytic method of the hydraulic support attitude is studied and verified using numerical calculation and simulation analysis, and the rigid-flexible coupling dynamic simulation model is built to study the various factors affecting the hydraulic support attitude. The research results of this paper can provide a theoretical basis and technical support for the attitude monitoring and control of hydraulic support. [ABSTRACT FROM AUTHOR]

Due to recent rainfall extremes and tropical cyclones that form over the Bay of Bengal during the pre- and post-monsoon seasons, the Nagavali and Vamsadhara basins in India experience frequent floods, causing significant loss of human life and damage to agricultural lands and infrastructure. This study provides an integrated hydrologic and hydraulic modeling system that is based on the Soil and Water Assessment Tool model and the 2-Dimensional Hydrological Engineering Centre-River Analysis System, which simulates floods using Global Forecasting System rainfall forecasts with a 48-h lead time. The integrated model was used to simulate the streamflow, flood area extent, and depth for the historical flood events (i.e., 1991–2018) with peak discharges of 1200 m3/s in the Nagavali basin and 1360 m3/s in the Vamsadhara basin. The integrated model predicted flood inundation depths that were in good agreement with observed inundation depths provided by the Central Water Commission. The inundation maps generated by the integrated modeling system with a 48-h lead time for tropical cyclone Titli demonstrated an accuracy of more than 75%. The insights gained from this study will help the public and government agencies make better decisions and deal with floods. [ABSTRACT FROM AUTHOR]

Estimating river flow is a critical step for planning and managing water resources. Since direct streamflow measurement is complex and time-consuming, managers rely on rating curves to estimate discharge. Due to this, it is crucial to develop accurate methods to estimate indirect streamflow. An estimated rating curve transforms recorded stages to discharge to obtain a streamflow time series. This study examines the estimation accuracy of the streamflow time series using the stage-discharge rating curve derived from geometric parameters and velocity parameter (U) based on inspiration from the Biot–Savart law. This model applies at least one year of measurement data for model training and the rest for model testing. Also, rolling cross-validation is performed to evaluate the trained model. The Markov Chain Monte Carlo method is used to calibrate and conduct the uncertainty analysis of the proposed model. Sensitivity analysis is also performed on model parameters (by the Sobol sensitivity indices) and Manning's roughness coefficient. Comparisons are made between findings from the proposed model and two classic and flow-area rating curves. The classic rating curve produces the stage-discharge rating curve without requiring cross-section geometry by fitting the appropriate curve between discharge and stage. The flow-area model calculates the stage-discharge rating curve by combining the wetted-area/stage and the cross-sectionally averaged velocity/stage functions. The studied models are tested in two rivers, Colorado in the US and Severn in the UK. Before using the observational data, outliers are removed using the Kernel density estimation method. The results show that the proposed method better estimates the streamflow than classic and flow-area rating curves. [ABSTRACT FROM AUTHOR]

The propagation of hydraulic fractures is highly influenced by the geological structure of the reservoir in unconventional reservoirs, such as natural fractures. In this paper, a new fluid–solid coupling dynamic model was built which presents the failure mechanism of hydraulic fracture with pre-existing simple and complex natural fractures. The cohesive element method and the maximum principal stress fracture criterion were used in the new model. An analysis was conducted to investigate the impact of various factors, including encounter angle, in situ stress, elastic modulus, and Poisson's ratio, on the propagation of hydraulic fractures. The simulation results indicate that the encounter angle and the in situ stress are the main factors affecting the fracture morphology. When the encounter angle and the in situ stress difference are small, hydraulic fractures propagate along natural fractures. When the elastic modulus is small, it is advantageous for the advancement of both hydraulic and natural fractures. The Poisson's ratio has a slight effect on the fracture propagation pattern. [ABSTRACT FROM AUTHOR]

The head loss substitution method with setting resistance rings is adopted in general physical model of long distance pressurized water diversion projects. Based on the hydraulic model test of Shenzhen Beikeng reservoir water diversion tunnel project, the head loss substitution effect and its variation law of the resistance ring under different Reynolds number, ring numbers and arrangements show: If Reynolds number (Re) is bigger than 0.32x105, it has less influence on local coefficient of head loss of the resistance ring and length of vortex region behind resistance ring; the decrease of parameter d/D (the diameter ratio of orifice and pipe) and the increase of the parameter L/D (the ratio of distance between rings and diameter of pipe) will enhance the head loss substitution effect; if parameter d/D is 0.8, L/D is 0.5, and the number of rings n is bigger than 2, the average local head loss coefficient Kd decreases with the increase of parameter n, and Kd does not change with the number of rings if the parameter n is bigger than 20. On this basis, the fitting curve between the ring number influence coefficient ε and the ring number n, the formulas of the total local head loss in the resistance substitution section and the length of the substitution pipe is derived. By analyzing the influence of different ring number on the length of vortex region, the length of transition section no less than 2.5D should be set behind the resistance substitution section to ensure the flow pattern returns to the unsubstituted state. [ABSTRACT FROM AUTHOR]

Nowadays, due to the complexity of water distribution systems and their large scale, their design, operation and maintenance require the use of optimal methods, which have become more important than in the past in improving their calibration. The most important issue in the simulation modeling of these systems is the consistency between the calculated and measured data. In the absence of the results of unaccounted water studies in the network, the use of statistical experimental methods is still needed as one of the main elements in model calibration. Based on this, the current research was conducted to investigate the effects of different patterns of unaccounted water based on the calculated water consumption patterns and to determine the optimal pattern of unaccounted water within the water distribution network covering the number of 6 ground reservoirs. The comparison of the statistical parameters showed that the use of the inverse model of the customers' consumption, which is not considered as a water model, for calibrating the hydraulic model of the distribution network, provides more acceptable limits for the closeness of the predicted values to the recorded values of the hourly output of the reservoirs, and therefore It is better to be used in studies related to planning and designs. [ABSTRACT FROM AUTHOR]

In tunnel boring projects, wear and tear in the tooling system can have significant consequences, such as decreased boring efficiency, heightened maintenance costs, and potential safety hazards. In this paper, a fault diagnosis method for TBM tooling systems based on SAV−SVDD failure location (SSFL) is proposed. The aim of this method is to detect faults caused by disk cutter wear during the boring process, which diminishes the boring efficiency and is challenging to detect during construction. This paper uses SolidWorks to create a complete three−dimensional model of the TBM hydraulic thrust system and tool system. Then, dynamic simulations are performed with Adams. This helps us understand how the load on the propulsion hydraulic cylinder changes as the TBM tunneling tool wears to different degrees during construction. The hydraulic propulsion system was modeled and simulated using AMESIM software. Utilizing the load on the hydraulic propulsion cylinder as an input signal, pressure signals from the two chambers of the hydraulic cylinder and the system's flow signal were acquired. This enabled an in−depth exploration of the correlation between these acquired signals and the extent of the tooling system failure. Following this analysis, a collection of normal sample data and sample data representing different degrees of disk cutter abrasions was amassed for further study. Next, an SSFL network model for locating the failure area of the cutter was established. Fault sample data were used as the input, and the accuracy of the fault diagnosis model was tested. The test results show that the performance of the SSFL network model is better than that of the SAE−SVM and SVDD network models. The SSFL model achieves 90% accuracy in determining the failure area of the cutter head. The model effectively identifies the failure regions, enabling timely tool replacement to avoid decreased boring efficiency under wear conditions. The experimental findings validate the feasibility of this approach. [ABSTRACT FROM AUTHOR]

Environmental flow assessment is an essential tool in water resource management. This study employs a holistic approach to evaluate the environmental flow in the Yen Basin, Thanh Hoa, Vietnam. Based on information gathered from a field survey, the Yen River system is divided into five reaches, and environmental objectives and ecological assets are identified in each reach. Hydrological and hydraulic mathematical models are applied to simulate the flow regime in the river, demonstrating their potential to assess environmental flow, especially in basins with limited data. The detailed results from the mathematical model facilitate selecting environmental flow components to address specific objectives for each river reach. By analyzing and selecting the flow regime, this study aims to ensure environmental protection while also considering basin development requirements, laying the groundwork for defining prescribed flow regimes in basin water management. [ABSTRACT FROM AUTHOR]

As a result of contamination intrusion's inherent vulnerability, water quality security has been an important issue within water distribution systems (WDSs). In order to detect (un)intentional intrusion events in a timely/effective manner, intensive studies have been undertaken to identify leakage detection and localization methodologies. It is possible to detect and localize leaks in water distribution systems using models-based methodologies. The purpose of this paper is to propose a novel leakage detection and leakage localization model that is based on the network hydraulic model. In order to solve the leakage problem, all hydraulic relationships have been modified and a new model has been developed. This model is developed based on head variation of network sensor nodes. This study utilized mathematical modeling based on the response surface methodology to detect leakages, in addition to detecting leaks; this method can also be used to assess the location of sensors. Consequently, in addition to developing a novel model, a new method is presented for assessing sensor placement in the present study. A leakage diagnosis benchmark dataset is used to demonstrate the proposed methodology and evaluate its effectiveness. Based on the final results, the presented method performed well and was highly accurate. [ABSTRACT FROM AUTHOR]

The interaction between a propagating hydraulic fracture (HF) and a pre-existing natural fracture (NF) embedded in saturated poroelastic rock formations is studied numerically in 2D plane–strain configurations. In this study, the phase-field method is further developed to be employed for modelling the HF propagation and the evolution of tensile and shear failure in geo-materials as gradient-type diffusive damaged zones. The shear slippage and dilation mechanisms inside the cemented NF are modelled using a Mohr–Coulomb–Griffith failure criterion that fitted in the framework of the phase-field fracture using appropriate energy functionals. The most important factors controlling the HF–NF interaction outcome are the approaching angle, differential in-situ stress, and hydro-mechanical characteristics of the NF. It is found out that higher tensile and shear strengths of the cemented NF are in favour of the crossing outcome when the differential stress is high enough to mobilise the resisting shear stresses against the slippage. Small hydraulic aperture (low hydraulic conductivity) for the NF is also in favour of the crossing outcome which helps to restrict the pressurised region local to the HF tip, lowering the possibility of shear slippage in the NF and the HF's diversion. It is also concluded that the injection rate and the viscosity of fracturing fluid are operative factors to be adjusted for increasing the chance of crossing, a critical element for successful operation of hydraulic fracturing for effective use of subsurface energy resources. Highlights: The phase-field method is developed for 2D modelling of mixed-mode tensile and shear failure as gradient-type diffusive damaged zones using Mohr–Coulomb–Griffith failure model. An extensive parametric study is conducted to identify the influential controlling factors in the interaction between a propagating hydraulic fracture (HF) and a pre-existing cemented natural fracture (NF) in plane–strain configurations. Hydro-mechanical characteristics of cemented NFs become important for intermediate approaching angles; the differential in-situ stresses and approaching angle are the most important controlling factors. Increasing the fluid injection rate can cause the HF to cross NFs with low permeability, whereas it can cause the HF to divert along the cemented NF that has a permeability much higher than the bulk rock. [ABSTRACT FROM AUTHOR]

Water supply systems (WSS) transport water from the source to the population, requiring a significant amount of energy, particularly for hydraulic pumps. To improve the efficiency of WSS, the use of hydraulic models and optimization algorithms can provide valuable insights for their operation and management. However, the efficient combination of these tools requires an effective and reliable sensitivity analysis. This work presents a novel and precise calculation of the sensitivities for the pump scheduling problem using a real continuous formulation and the extended period simulation (EPS) hydraulic analysis, as used in the generality of hydraulic simulators, such as EPANET. The work was validated through comparison with the finite-difference method (FDM) in two numerical case studies: a simple pump-tank network and the AnyTown Modified benchmark. For the last case study, an optimization process was carried out comparing the results obtained by the FDM and the analytical approach previously validated. The analytical sensitivities were found to be more accurate and require lower computational resources than the alternative approaches. [ABSTRACT FROM AUTHOR]

For oil and gas exploitation engineering, it is significant to study the interaction between hydraulic fracture (HF) and natural fracture (NF). An extended peridynamic (PD) model for hydraulic fracture analysis is presented, in which the PD pairwise force with the bond rotation is considered, fluid pressure is applied at fracture surfaces with broken bonds, and the critical stretch and critical relative rotation bond failure criteria are derived for Mode I and Mode II fractures of shale reservoir, respectively. Then, numerical examples of hydraulic fracturing of concrete and shale are analyzed using the PD model. The proposed model can well predict the interaction behaviors between HF and NF, and simulation results show that the larger the in situ stress difference and approach angle, the easier it is for the hydraulic fractures to cross the natural fractures. [ABSTRACT FROM AUTHOR]

Collapsible and expansive soils cover almost one-fifth of the Earth's land surface. The key feature of these categories of problematic soils is the considerable volumetric strain upon saturation under constant stress. However, most studies on saturated hydraulic conductivity of soils assumed no volumetric tendency of the specimen subjected to water saturation. As a result, a significant error may arise from this assumption in collapsible and expansive soils. In accordance with the standard testing protocols, no modeling approaches regarding the hydraulic conductivity can consider the significant changes in void ratio caused by the saturation-induced collapse or expansion phenomena. Therefore, this study aims to introduce a new modeling framework for the saturated hydraulic conductivity of problematic soils with a marked volumetric tendency upon saturation. Accordingly, 36 tests are conducted on two typical soil types representing collapsible and expansive soils with three levels of saturation-induced volume changes and a wide range of void ratios. All tests are conducted in a low-compliance double-cell twin-burette triaxial permeameter. Afterward, new modeling frameworks based on the Kozeny–Carman model are developed to account for the collapse and swell potentials. The results reveal unique functions between the saturated hydraulic conductivity and the reliable void ratio for both collapsible and expansive soils. Eventually, the performance of new models is validated against some independent data sets retrieved from the literature and discussed. Collapsible and expansive soils cover about one-fifth of the Earth's surface. These soils are characterized by high deformability once a near-saturation condition is approached. As a result, the corresponding hydraulic conductivity can be subject to sever variations because of significant microstructural modification induced after inundation or hydration. However, most of the measuring devices and modeling frameworks fail to take into account the saturation-induced volume changes of problematic soils in estimation of permeability versus void ratio function. Therefore, the significance of volumetric strain during the saturation procedure was first revealed and highlighted through conducting 36 permeability experiments in a low-compliance triaxial permeameter on both collapsible and expansive soils, with various deformation potentials in response to full saturation. Afterward, new models pertaining to both types of soils were developed based on the Kozeny–Carman model with two additional physics-based parameters reflecting the deformation tendency of a given soil. Indeed, the merit of the new modeling framework is the incorporation of collapse and swell potentials into the void ratio function, which can be easily measured with a conventional oedometer cell. Eventually, the proposed modeling approach was validated against measurements conducted in this study as well as several data sets retrieved from the literature. [ABSTRACT FROM AUTHOR]

This research evaluates natural flood management strategies in a mountain basin, the Olivares-Minitas creek in Manizales, Colombia, to quantify the effectiveness of their application in reducing floods. Hydraulic and hydrological modeling was performed simultaneously in Iber software. Multiple scenarios were proposed for three natural flood management alternatives: (1) making room for the channel, eliminating contractions and structures limitations, (2) changing the vegetation cover of the upper part of the basin, increasing the ground roughness, and (3) reconnect the stream with their floodplains, allowing the stream to dissipate flow and energy. Applying these strategies, the simulations resulted of the decrease the high discharges and the delay in peak times for the hydrographs. In conclusion, from natural solutions like rehabilitating, recovering the water body, and their ecosystem, is possible to manage and reduce the flooding risk, Attaining benefits through long-term reduction of flooding and enhancement of the river and its ecosystem. [ABSTRACT FROM AUTHOR]

This paper presents a holistic approach to address the challenges associated with deploying laboratory-derived hydraulic models in real operational conditions within Urban Water Systems (UWS). The underlying methods and tools are tested and validated using real-world data from the conveyance system serving the city of Athens, Greece. Initially, a novel data repair mechanism is developed, to rectify inconsistencies in time series. Subsequently, algorithmic techniques are applied to identify the most suitable datasets for calibration purposes. Furthermore, a grey-box procedure is developed to adjust key hydraulic modelling parameters, following a modular calibration procedure and aligning them with the specific characteristics of the UWS under study. The findings of this study provide valuable insights for effectively adapting and implementing laboratory-derived hydraulic models in real-world UWS scenarios, enabling better decision-making and management strategies for complex hydro-systems under challenging operational conditions. [ABSTRACT FROM AUTHOR]

Field measurement of the bed roughness of tropical tidal rivers is a long and expensive process. In this study, we quantified the roughness coefficient from the acoustic Doppler current profiler (ADCP) measurements considering flow characteristics along a 240 km length of the Vu Gia Thu Bon River system, in central Vietnam. Our approach entailed the application of the logarithmic velocity distribution trend of turbulent flows to determine the bottom roughness height. Then, we applied the equation suggested by Strickler (1923) to calculate the Manning roughness coefficient. The TELEMAC-2D hydraulic model was then used to simulate the effect of the roughness coefficient on the estimated water level. Despite its uncertainty, the estimated bed roughness was sufficient for the accurate calculation of the hydraulic variables. Compared to those in previous research, the statistical indicators showed good performance in the first simulation process during both the calibration and validation periods along the river system. [ABSTRACT FROM AUTHOR]

Frequent floodings in Semarang City have generated increasing damages and losses in property and life quality. The cause of flooding is related to the coupled impacts of land subsidence, hydraulics hazards along with poor drainage and water retention systems. This paper studies the most recent flooding hazards caused by hydrological origins (i.e., river discharge, tidal) and land subsidence. In the study, riverine origin of flooding is simulated with the help of HEC-RAS 2D, while the tidal origin is simulated to high highest water level. However, due to the absence of the most recent topographic data, the role of land subsidence is measured by estimating the vertical changes of digital elevation model taken from Sentinel 1A. Flooding extent, in terms of depth and coverage, is verified based on satellite imagery Sentinel-2 which is cloud-processed using Google Earth Engine (GEE) and field survey. Fluvial flood is simulated with several boundary condition scenarios using combinations of 5-, 25-, or 50-year return periods of flood which is integrated with mean sea level (MSL) or high highest water level (HHWL) tides. Those boundary conditions are then incorporated into different terrains, namely LiDAR, DEMNAS, and TerraSAR DEM, to see how different digital elevation models (DEMs) can impact model sensitivity. By overlaying model outputs and land cover map, it can be concluded that settlements and water bodies are among the most potentially affected areas, covering up to 17 km2. This study is expected to help policymakers make a primary assessment of combined tidal and fluvial flood hazard through mitigation and adaptation measures. [ABSTRACT FROM AUTHOR]

Tidal inlet structures are engineering projects with associated benefits related to flood control, water quality enhancement, and coastal protection. This study analyzes the performance of hydraulic gates on a stabilized inlet in estuarine systems by developing a simplified hydraulic model that considers inlet and outlet water levels. The proposed model was applied to the stabilized tidal inlet structure in Cartagena de Indias, Colombia. This model offers a practical tool for engineers and designers operating estuarine systems. The analysis focuses on the coastal lagoon of Ciénaga de la Virgen. The proposed model was successfully calibrated using two water sensors, with extreme input and outlet flow rates of approximately 260 m3/s and 110 m3/s, respectively. The average daily output volume in the system is 3,361,000 m3, while the average daily input volume is 3,200,000 m3. Consequently, the manipulation of the opening gates results in a decrease in the estuarine water level, potentially by as much as 25 cm, which local authorities can use to make decisions to reduce extreme water levels during flooding events. [ABSTRACT FROM AUTHOR]

With the increasing urbanization rate, higher demand is placed on drainage systems, necessitating analysis of their risk profiles. While many studies focus on the individual hydraulic modeling of stormwater and wastewater systems when considering operational risks, they often overlook the exacerbating effects of combined stormwater and wastewater flows on each other's risks. In this study, we constructed a model of the combined stormwater and wastewater drainage system in Lijiao, Guangdong Province. We analyzed the operational risks of both stormwater and sewage networks in different scenarios, focusing on full-load pipes, overload pipes, node overflows, and minimum flow velocities. Furthermore, we compared the exacerbating effects of sewage and stormwater on each other's network operational risks. Simulation results indicated that, for sewage networks with combined sewer sections, the lengths of full-load pipes and overload pipes increased by an average of 27.4% and 16.3%, respectively, during rainy weather scenarios compared to dry weather. After considering the inflow of sewage into combined sewer sections, the average length of full-load pipes increased by 3.8 km, overload pipe length increased by 1.1 km, and overflow volume increased by 2.26 × 104 m3. As the return period of rainfall events increases, these inter-system impacts gradually diminish. Therefore, when modeling drainage systems and assessing operational risks, particularly during low return period rainfall events, the inclusion of both stormwater and sewage in combined sewer networks should be comprehensively considered. [ABSTRACT FROM AUTHOR]

The middle reach of the Helmand River is prone to floods, and flood hazard analysis is necessary to manage the flood risk. As the study site is a less-developed basin where available geographical and hydrological data are limited, we must utilize available limited data to conduct the flood hazard analysis. A frequency analysis of the annual peak flow rate was performed using available hydrological data for making representative flood hydrographs. A land-use map is derived by classifying recent Landsat images. Digital elevation model derived by Advanced Land Observing Satellite, roughness coefficient correlated with the land-use map, and the representative flood hydrographs are fed into hydraulic model HEC-RAS 2D. Flood inundation area, depth, and velocity for different flood return periods are estimated. Based on local hazard intensity and vulnerability, risk maps for evacuation and vulnerability of crops on the floodplain are obtained. Spatial flood risk characteristics differ at the upstream and downstream reaches because of distinct floodplain topography. Flood countermeasures for each reach are proposed based on the spatial characteristics of the flood risk. To provide risk information for residents within the region, the flood hazard, risk, and damage maps derived in this study are published as a web map application and a mobile native application. [ABSTRACT FROM AUTHOR]