Journal of Hydro-environment Research最新文献

{"title":"An iterative hydraulic design methodology based on numerical modeling for piano key weirs","authors":"Mete Koken,&nbsp;Ismail Aydin,&nbsp;Serhan Ademoglu","doi":"10.1016/j.jher.2022.01.002","DOIUrl":"10.1016/j.jher.2022.01.002","url":null,"abstract":"<div><p>Piano Key Weir (PKW) is a special type of overflow weir which provides an improved discharge capacity with its increased crest length. Increased discharge capacity makes this weir an attractive alternative in the rehabilitation of existing spillways. After the introduction of this new weir type, many experimental and numerical studies are conducted to understand the effect of the numerous geometrical parameters on the discharge capacity. However, empirical discharge formulas suggested by different researchers are not conforming to a unique expression mostly due to dependence on the experimental conditions from which they are derived. A numerical approach is used in the present study to investigate the dependence of discharge capacity of a PKW unit on several geometric parameters. Numerical models are developed and three-dimensional velocity fields are computed using FLOW-3D® software. Discharge efficiency of a PKW over an equivalent linear sharp-crested weir is evaluated within the practical range of parameters from 145 numerical solutions for 29 different PKW models. Numerically obtained data is used to form dimensionless expressions for the weir height and length as function of discharge efficiency which are proposed to facilitate an iterative numerical solution to meet the design requirements of a given project. This approach allows cost optimization while dimensioning the PKW for the required hydraulic capacity. The design procedure based on iterative numerical solutions is described and exemplified.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 131-141"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45908784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the turbulence characteristics in developed and developing rough narrow open-channel flow","authors":"M. Mahananda ,&nbsp;P.R. Hanmaiahgari ,&nbsp;Ram Balachandar","doi":"10.1016/j.jher.2021.11.003","DOIUrl":"10.1016/j.jher.2021.11.003","url":null,"abstract":"<div><p>An analytical power-law for velocity distribution is developed and validated using experimental results for rough, narrow open-channel flows. In addition, an empirical power-law for the mean velocity distribution is also proposed. To this end, experiments were conducted to investigate the turbulence characteristics in developing and fully developed narrow open-channel flows over a fixed continuous rough bed. Instantaneous 3-D velocities were acquired using a Nortek VectrinoPlus down looking acoustic Doppler velocimeter at streamwise intervals of 0.5 m along the centerline of the flume. Using the experimental data, shape factors and frictional characteristics in narrow open-channel flow were analysed. In addition, this paper investigated changes in the turbulence anisotropy and the decay of turbulence along the mid-depth of the hydraulically rough flow. The new analytical power-law equation developed in this paper accurately describes the fully developed velocity profile in narrow open-channel flow with the dip phenomenon. Reynolds number and aspect ratio significantly influenced the turbulence characteristics in the upper half of the flow field. The decreasing turbulence intensities at mid-depth along the flow developing region demonstrate the attainment of isotropic turbulence as the flow development occurs in the narrow open-channel.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 17-27"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46227724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DEM resolution effects on machine learning performance for flood probability mapping","authors":"Mohammadtaghi Avand ,&nbsp;Alban Kuriqi ,&nbsp;Majid Khazaei ,&nbsp;Omid Ghorbanzadeh","doi":"10.1016/j.jher.2021.10.002","DOIUrl":"10.1016/j.jher.2021.10.002","url":null,"abstract":"<div><p>Floods are among the devastating natural disasters that occurred very frequently in arid regions during the last decades. Accurate assessment of the flood susceptibility mapping is crucial in sustainable development. It helps respective authorities to prevent as much as possible their irreversible consequences. The Digital Elevation Model (DEM) spatial resolution is one of the most crucial base layer factors for modeling Flood Probability Maps (FPMs). Therefore, the main objective of this study was to assess the influence of the spatial resolution of the DEMs 12.5 m (ALOS PALSAR) and 30 m (ASTER) on the accuracy of flood probability prediction using three machine learning models (MLMs), including Random Forest (RF), Artificial Neural Network (ANN), and Generalized Linear Model (GLM). This study selected 14 causative factors in the flood as independent variables, and 220 flood locations were selected as dependent variables. Dependent variables were divided into training (70%) and validation (30%) for flood susceptibility modeling. The Receiver Operating Characteristic Curve (ROC), Kappa index, accuracy, and other statistical criteria were used to evaluate the models' accuracy. The results showed that resolving the DEM alone cannot significantly affect the accuracy of flood probability prediction regardless of the applied MLM and independently of the statistical model used to assess the performance accuracy. In contrast, the factors such as altitude, precipitation, and distance from the river have a considerable impact on floods in this region. Also, the evaluation results of the models showed that the RF (AUC_12.5,30m = 0.983, 0.975) model is more accurate in preparing the FPM than the ANN (AUC_12.5,30m = 0.949, 0.93) and GLM (AUC_12.5,30m = 0.965, 0.949) models. This study's solution-oriented findings might help water managers and decision-makers to make the most effective adaptation and mitigation measures against potential flooding.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 1-16"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1570644321000769/pdfft?md5=13acefc3fd1e4c0759676b3882f1f2d6&pid=1-s2.0-S1570644321000769-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43538073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study of obstacle and bed roughness effects on behavior of turbidity current","authors":"Sara Baghalian ,&nbsp;Masoud Ghodsian","doi":"10.1016/j.jher.2021.11.002","DOIUrl":"10.1016/j.jher.2021.11.002","url":null,"abstract":"<div><p>Laboratory experiments were carried out to study the behavior of turbidity current under subcritical approach flow condition. In order to study the effects of solid obstacle and bed roughness on turbidity current, 24 experiments were conducted. Two trapezoidal macro-roughness elements with 0.01 m and 0.03 m height and three triangular obstacles with 0.1 m to 0.3 m height were used. The parameters such as front velocity, velocity profiles, body height, flow discharge, suspended load transport rate and efficiency of the obstacle were determined. It was found that under subcritical flow regime, the main portion of the turbidity current over the rough bed is controlled, if the obstacle height is 2–3 times of the body height. The growth of the front height depends on the inlet sediment concentration, the roughness elements and the obstacle height. The front velocity upstream of the obstacle over the smooth bed is independent of the obstacle height and significantly influenced by roughness elements. Simultaneous use of the bed roughness and obstacle significantly reduces the front velocity downstream of the obstacle. The flow discharge per unit width significantly decreases downstream of the obstacle. Simultaneous use of an obstacle and roughness elements decreases the flow discharge per unit width by about 90%. An obstacle with height equal to 0.75 of the initial height of the turbidity current with the smooth bed blocks about 65% of the suspended sediment. While, simultaneous use of the obstacle and the roughness elements blocks about 95% of the suspended sediment.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 77-90"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46806065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of horizontal eddy viscosity and bottom friction coefficients on morphodynamic evaluations","authors":"N. Saichenthur,&nbsp;K. Murali,&nbsp;V. Sundar","doi":"10.1016/j.jher.2021.12.005","DOIUrl":"10.1016/j.jher.2021.12.005","url":null,"abstract":"<div><p>The horizontal eddy viscosity (ε) and bottom friction coefficient (<em>K_br</em>) are important hydrodynamic parameters in the computation of flow fields that dictate the morphodynamics. The effect of the variations in ε and <em>K_br</em> as well as their combination on the prediction of hydrodynamics and morphodynamics in the Cochin harbor and adjoining nearshore area (9.9312° N, 76.2673° E) has been investigated in detail. A tidal circulation model to solve the shallow water equation is applied with the different parameterizations of ε and <em>K_br</em>. In order to understand its effect, ε is expressed as a function of depth averaged velocity and length scale of computation mesh, whereas <em>K_br</em> is expressed as a function of depth. The validation of the model is carried out with the measured currents. The improvement in the hydrodynamic and morphodynamic predictions is demonstrated by implementing the spatially and temporally varying ε The predictions are further improved by implementing a spatially varying <em>K_br</em>. It is seen that the simulations with varying ε and <em>K_br</em> predict the morphodynamic behavior close to the field values. The performance of the model predictions is discussed in terms of R², RMSE and BSS (Brier Skill Score).</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 102-115"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41883177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the effects of human influences on water quality and quantity in the Zarrineh River Basin, Iran","authors":"Sahere Golzari ,&nbsp;Hamid Zare Abyaneh ,&nbsp;Naghmeh Mobarghaee Dinan ,&nbsp;Majid Delavar ,&nbsp;Paul Daniel Wagner","doi":"10.1016/j.jher.2021.11.001","DOIUrl":"10.1016/j.jher.2021.11.001","url":null,"abstract":"<div><p><span>This study aims to analyze the environmental and economic impacts of land use change and water abstraction in the Zarrineh River basin, which is Lake Urmia’s main inflow source in the north-west of Iran. The Soil &amp; Water Assessment Tool (SWAT) is used to model water quantity and quality in the basin. Environmental Kuznets Curves (EKC) are used to assess the relationship between environmental degradation and the development of the agricultural sector. Two scenarios were employed to identify the effects of dam construction and land use change on stream flow, evapotranspiration, </span>groundwater recharge and nitrate loads in the area. The SWAT model showed a satisfactory to very good performance for monthly stream flow at most of the gauges in calibration and validation periods as well as a reasonable performance for nitrate loads. The estimated EKC indicates that the environmental degradation in the inverted U-shape that has passed its peak and the rate of degradation has decreased. Based on the scenarios, the dam has a strong impact on nitrate loads in the basin and water inflow into Lake Urmia. Results verify that human influences have had negative impacts on the Zarrineh River basin. In particular, the extensive development of the agricultural sector has not only drastically reduced the inflow of water to Lake Urmia accelerating the drying up of the lake, but it has also increased nitrate loads. Therefore, it can be recommended to take counter measures within the catchment area to improve the ecological status of Lake Urmia.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 51-63"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47924158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical and numerical modeling of swirling flow in a scroll vortex intake","authors":"S.N. Chan ,&nbsp;Jiuhao Guo ,&nbsp;Joseph H.W. Lee","doi":"10.1016/j.jher.2021.11.004","DOIUrl":"10.1016/j.jher.2021.11.004","url":null,"abstract":"<div><p>Scroll vortex intakes are hydraulic structures commonly used in water supply, drainage and sewerage systems. Water flows into the intake via an eccentric approach channel and a vortex chamber imparts swirl to the flow, leading to a stable air core vortex along the dropshaft. Although much effort has been devoted to investigate the scroll vortex flow, yet the understanding on its hydraulic characteristics is still far from complete due to a lack of detailed velocity field measurements. This paper presents the first comprehensive measurement of the three-dimensional (3D) flow field of a scroll vortex intake using non-intrusive Laser Doppler Anemometry (LDA). A validated 3D Computational Fluid Dynamics (CFD) model with the Volume-Of-Fluid (VOF) method is developed for interpreting the measurement. It is found that the vortex flow in the scroll chamber resembles a free vortex and the circulation is approximately equal to that at the chamber inlet, with a thin bottom boundary layer. The vortex flow at the bellmouth outlet possesses a circulation constant smaller than that in the chamber, and its vertical velocity component is approximately constant across the flow thickness.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 64-76"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43537186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial (January 2022)","authors":"","doi":"10.1016/j.jher.2022.01.001","DOIUrl":"10.1016/j.jher.2022.01.001","url":null,"abstract":"","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Page 142"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45952219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation of the effects of contraction on tsunami-induced forces and pressures on a box section bridge","authors":"Farzad Farvizi ,&nbsp;Bruce W. Melville ,&nbsp;Asaad Y. Shamseldin ,&nbsp;Seyedreza Shafiei","doi":"10.1016/j.jher.2021.12.004","DOIUrl":"10.1016/j.jher.2021.12.004","url":null,"abstract":"<div><p>Many bridges that lie within possible tsunami inundation zones are critical links in transport networks. Some efforts have been made to determine the effects of tsunamis on bridges, but only a limited range of published design guidelines are available. Therefore, it is necessary to further investigate the effects of tsunamis on bridges. In the current study, physical modeling experiments were carried out to measure bore impact forces and pressures for various tsunami bore strengths on a bridge deck with different abutment types (wing wall and spill-through) and different opening and submergence ratios. The experiments were conducted in a wave flume with dimensions of 14 × 1.2 × 0.8 m (length × width × height), equipped with an automatic gate designed to generate a tsunami bore. The horizontal and vertical forces showed an increasing trend with increasing submergence ratio for both types of abutment. However, the horizontal force showed a decreasing trend as the opening ratio decreased, while the vertical force initially increased as the opening ratio decreased, until it reached a peak value, and then it started to decrease. The overall shapes of the results for both types of abutment are similar, with higher values for spill-through abutments due to their lower energy dissipation rates. Based on the experimental data, empirical equations are proposed for estimation of tsunami loads as a function of opening and submergence ratios.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"40 ","pages":"Pages 116-130"},"PeriodicalIF":2.8,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49176102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-term River streamflow modeling using Ensemble-based additive learner approach","authors":"Khabat Khosravi ,&nbsp;Shaghayegh Miraki ,&nbsp;Patricia M. Saco ,&nbsp;Raziyeh Farmani","doi":"10.1016/j.jher.2021.07.003","DOIUrl":"10.1016/j.jher.2021.07.003","url":null,"abstract":"<div><p>Accurate streamflow (Q_t<span>) prediction can provide critical information for urban hydrological management strategies such as flood mitigation, long-term water resources management, land use planning and agricultural and irrigation operations. Since the mid-20th century, Artificial Intelligence (AI) models have been used in a wide range of engineering and scientific fields, and their application has increased in the last few years. In this study, the predictive capabilities of the reduced error pruning tree (REPT) model, used both as a standalone model and within five ensemble-approaches, were evaluated to predict streamflow in the Kurkursar basin in Iran. The ensemble-approaches combined the REPT model with the bootstrap aggregation (BA), random committee (RC), random subspace (RS), additive regression (AR) and disjoint aggregating (DA) (i.e. BA-REPT, RC-REPT, RS-REPT, AR-REPT and DA-REPT). The models were developed using 15 years of daily rainfall and streamflow data for the period 23 September 1997 to 22 September 2012. A set of eight different input scenarios was constructed using different combinations of the input variables to find the most effective scenario based on the linear correlation coefficient. A comprehensive suite of graphical (time-variation graph, scatter-plot, violin plot and Taylor diagram) and quantitative metrics (root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliff efficiency (NSE), Percent of BIAS (PBIAS) and the ratio of RMSE to the standard deviation of observation (RSR)) was applied to evaluate the prediction accuracy of the six models developed. The outcomes indicated that all models performed well but the AR-REPT outperformed all the other models by rendering lower errors and higher precision across a number of statistical measures. The use of the BA, RC, RS, AR and DA models enhanced the performance of the standalone REPT model by about 26.82%, 18.91%, 7.69%, 28.99% and 28.05% respectively.</span></p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"39 ","pages":"Pages 81-91"},"PeriodicalIF":2.8,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43089837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}