Journal of Hydro-environment Research最新文献

{"title":"Self-aeration on large dam spillways during major floods","authors":"Hubert Chanson","doi":"10.1016/j.jher.2024.03.002","DOIUrl":"https://doi.org/10.1016/j.jher.2024.03.002","url":null,"abstract":"<div><p>In a spillway chute flow, the upstream flow is typically non-aerated and the flow becomes self-aerated when the turbulent stresses acting next to the water surface exceeds the combined resistance of gravity and surface tension. The inception region of air entrainment is a rapidly-varied region characterised by the transition from a monophase water to two-phase air–water flow. In this contribution, field observations were conducted at large dam spillways during major flood events, with a focus on prototype data for discharges between 100 m³/s and 6,000 m³/s and Reynolds numbers between 2.6 × 10⁶ to 1.1 × 10⁸. The onset of self-aeration was a complicated three-dimensional transient process, and the dimensionless location of the inception region was a function of the Reynolds number. Surface velocities obtained with an optical technique showed that the streamwise surface velocities were close to theoretical estimates, and the streamwise surface turbulent intensities in excess of 100 %, consistent with self-aerated measurements in laboratory. The current findings yield a couple of seminal questions: (a) what do we know about prototype spillway operation during major floods? (b) how large the Reynolds number of a prototype flow needs to be truly representative of large dam spillway self-aerated flows during major flood events?</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"54 ","pages":"Pages 26-36"},"PeriodicalIF":2.8,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140191987","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":"Investigation of turbulent flow induced by particle sedimentation using RIM-PIV","authors":"Eiji Harada,&nbsp;Takumi Tazaki,&nbsp;Hitoshi Gotoh","doi":"10.1016/j.jher.2024.03.001","DOIUrl":"https://doi.org/10.1016/j.jher.2024.03.001","url":null,"abstract":"<div><p>The spatiotemporal structure of the flow field during particle–cloud sedimentation has not been sufficiently investigated. In this study, experiments on the sedimentation process of particle clouds in water are conducted using hydrogel particles with a refractive index similar to that of water as the settling particles. The flow field during the sedimentation process of particle clouds in water is measured using particle image velocimetry (PIV). Although the measurement conditions in this study are restricted to one condition owing to the limitations of the measurable area by our PIV system and the available hydrogel particles, the measurement target is novel because it has not been measured so far. The spatiotemporal structure of the turbulent flows is investigated by analyzing the turbulent flows induced by the sedimentation particles using the PIV system. Furthermore, the turbulent structure of the vortex formed by particle sedimentation is examined.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"54 ","pages":"Pages 13-25"},"PeriodicalIF":2.8,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140163505","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":"Deciphering the effect of variation in slope on flow characteristics in a vertical slot fishway","authors":"Hao Yuan ,&nbsp;Boyu Chen ,&nbsp;Qian Sun ,&nbsp;Chunhang Xie ,&nbsp;Xiaolong He","doi":"10.1016/j.jher.2024.02.005","DOIUrl":"https://doi.org/10.1016/j.jher.2024.02.005","url":null,"abstract":"<div><p>The effects of a vertical slot fishway slope (with slope values from 1.5% to 6%) on a flow field are numerically investigated, using a re-normalization group <em>k</em> – <em>ε</em> model. The distribution of the velocity, turbulence kinetic energy (<em>TKE</em>), average energy dissipation rate per unit volume (<em>E</em>), and vorticity for different slopes are systemically explored. The results indicate that, with an increase in slope, the appearance of downward flow in conjunction with an increase in vertical velocity results in three-dimensional flow characteristics. The recirculation region in <em>H</em>_s, at a 6.0% slope, was 20.9% less than that at a 1.5% slope. Meanwhile, the flow velocity in the vertical slot region grew with increasing slope, which would limit the passage of fish with burst speed lower than the velocity in the vertical slot region. The <em>TKE</em> and <em>E</em> may locally exceed the threshold at larger slopes. Furthermore, vorticity distribution shows little variability with increasing slope, but may interfere with the equilibrium of the fish in the vertical slot region. In addition, the change in water level has little effect on the flow field, which is changed by the increase in slope. These findings can aid vertical slot fishway designs especially in terms of the efficiency of fish passage.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"54 ","pages":"Pages 1-12"},"PeriodicalIF":2.8,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140041683","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":"Spur dike layouts impact on upstream flow conditions during flood wave movement","authors":"Shabnam Moghispour ,&nbsp;Salah Kouchakzadeh","doi":"10.1016/j.jher.2024.02.004","DOIUrl":"https://doi.org/10.1016/j.jher.2024.02.004","url":null,"abstract":"<div><p>Despite the widespread application of spur dikes in river training projects, the performance of the structure during flood events and its impacts on unsteady flow conditions have rarely been studied. In this experimental investigation, the influences of twelve unsubmerged unilateral and bilateral spur dike layouts on upstream flow conditions during flood movements were examined. Three hydrographs with varying unsteadiness intensities were generated and applied to all layout tests, including the no-spur condition for comparison purposes. The results revealed that discharge directly affected changes in flow depth upstream of the spur dike, while the flow rate trend exerted inverse influences. The Keulegan-Carpenter number was modified to assess the impact of unsteadiness intensity on the rating curve loop. Stage hysteresis analysis demonstrated an increase of more than thirty times compared to the no-spur scenario, highlighting the elevated risk of flooding in the upstream reach while delaying peak flood arrival time. This has implications for flood risk management and warning programs. The results underscore the significance of considering not only peak discharge but also unsteadiness intensity in spur dike design.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"53 ","pages":"Pages 44-57"},"PeriodicalIF":2.8,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140014358","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 study on surface wave interaction with submerged tensioned barriers using IoT image processing","authors":"Cheng Bi ,&nbsp;Yong Jia Toh ,&nbsp;Adrian Wing-Keung Law ,&nbsp;Mao See Wu","doi":"10.1016/j.jher.2024.02.003","DOIUrl":"10.1016/j.jher.2024.02.003","url":null,"abstract":"<div><p>The present study investigated experimentally the dynamic interactions between surface waves and submerged vertical tensioned barriers with full and partial penetrations. The range of tension for the barrier was set within the flexible membrane regime in the experiments which measurements have not been reported in the literature so far. In addition, an extensive Internet of Things (IoT) system with five GoPro cameras was developed for the measurements to quantify both the surface wave transformation as well as dynamic response of the barrier. The cameras were synchronized through the IoT system to cover the entire wave flume, and the recorded videos were converted to spatial and temporal data using image processing techniques. The experimental results were found to agree with the analytical predictions based on the linear wave theory reasonably well. In particular, the measured reduction in the tensioning effect on the wave transmission and reflection with decreased barrier length was in close argument with the predictions. Similar good agreement was also observed for the dynamic response of the tensioned barrier during the wave interaction. However, additional energy loss was noted in the experiments possibly due to energy dissipation at the boundary ends of the experimental barrier and wave-induced flow separation with partial penetration which are not considered in the analytical analysis.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"53 ","pages":"Pages 28-43"},"PeriodicalIF":2.8,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139924981","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":"Refined analysis of flood-regional composition under changing environment in the middle reach of Hanjiang River","authors":"Pengxin Deng ,&nbsp;Changjiang Xu ,&nbsp;Jianping Bing ,&nbsp;Leizhi Wang ,&nbsp;Lingjie Li","doi":"10.1016/j.jher.2024.02.002","DOIUrl":"10.1016/j.jher.2024.02.002","url":null,"abstract":"<div><p>To investigate the flood-regional composition under changing environmental conditions in the middle reach of Hanjiang River (MHR), a data-driven hydrological simulation model and its related quantitative methods were developed. The flood-regional composition of Huangzhuang(HZ) in the MHR was quantitatively analyzed, and the influence of environmental changes on river flood routing was discussed. The primary research findings are as follows: ① A hydrological simulation model based on support vector regression machine (SVRM) is constructed to simulate the daily average flow process of HZ from 1965 to 2021. The Nash-Sutcliffe Efficiency (NSE) coefficient achieved values above 0.95, and the overall relative error (RE) was within ± 1 %, indicating excellent simulation performance. ② A quantitative analysis method has been proposed to identify the composition of flood areas. The results indicate that the upper reach of Hanjiang River (UHR) is the primary contributor to floods in the MHR, accounting for 60.62 % to 78.05 % of the total. The Tangbai River (TR) contributed between 14.1 % and 27.4 %, whereas the Nan River had a smaller contribution of only 6.83 % to 8.85 %. ③ Trend analysis indicates that the proportion of floods originating from the UHR increases in the summer flood season and decreases in the autumn flood season, while those changes of TR and Nanhe River (NR) are coincidental, especially in the autumn flood season, the proportion of floods in the TR increases significantly. The impact of floods from the UHR and TR cannot be ignored when implementing flood control measures. ④ A comprehensive analysis method has been proposed to quantify the integrated impacts of environmental changes. The results show that environmental changes had a relatively minor impact on flood routing and its flood-regional composition. However, they did affect the flood propagation process, resulting in earlier occurrences in peak flow, increased in peak discharge, and rapid rise and fall of floodwaters for floods exceeding 12,000 m³/s. These research findings provide strong foundational support for designing flood-regional, as well as flood control and disaster reduction systems in the MHR.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"53 ","pages":"Pages 15-27"},"PeriodicalIF":2.8,"publicationDate":"2024-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139924980","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":"Numerical simulation of the critical hydraulic gradient of granular soils at seepage failure by discrete element method and computational fluid dynamics","authors":"Yuqi Li ,&nbsp;Liangchen Xu ,&nbsp;Zhuyin Ma ,&nbsp;Bingbing Ma ,&nbsp;Junhao Zhang","doi":"10.1016/j.jher.2024.02.001","DOIUrl":"https://doi.org/10.1016/j.jher.2024.02.001","url":null,"abstract":"<div><p>Seepage failure is a common problem in engineering, and the calculation and analysis of critical hydraulic gradient are of great significance for the safety and protection of engineering. Based on the principle of discrete element method and computational fluid dynamics, the fluid–solid coupled models were established to study the critical hydraulic gradient and particle loss rate of granular soils at seepage failure. The evolution of seepage failure was divided into four stages: seepage development stage, local damage stage, volume expansion stage and overall damage stage. The validity of numerical simulation was demonstrated by comparing the critical hydraulic gradient obtained by numerical simulation and by Terzaghi’s formula. According to the fabric damage and flow velocity variation of the models at seepage failure, the influences of model size and particle size on the critical hydraulic gradient and particle loss rate were analyzed. The results indicate that critical hydraulic gradient and particle loss rate were not sensitive to changes in model size. A wide particle size distribution range resulted in large critical hydraulic gradient and small particle loss rate at seepage failure. The discrete element numerical simulation can not only be used to determine the critical hydraulic gradient of geotechnical and hydraulic engineering, but also offer a visual portrayal of the evolution of seepage failure, serving as an important complement to comprehend the intricate microscopic mechanisms underlying soil seepage failure.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"53 ","pages":"Pages 1-14"},"PeriodicalIF":2.8,"publicationDate":"2024-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139699706","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":"Conjugation of deep learning and de noising data methods for short-term water turbidity forecasting","authors":"Shahram Mousavi","doi":"10.1016/j.jher.2023.12.002","DOIUrl":"10.1016/j.jher.2023.12.002","url":null,"abstract":"<div><p>Water turbidity is a critical index of water quality due to its high correlation with the five main water quality parameters (electrical conductivity, nitrogen, dissolved oxygen, phosphorus, and pH). The exact measurement of water turbidity is a difficult process because many conditions affect the reading of turbidity. Although many researchers applied decomposition-based techniques for preprocessing, it is difficult to use these approaches in real estimation because the newly acquired data greatly affect the initial decomposed subsequent values. In this study, the threshold-based wavelet denoising method, as a data pre-processing, coupled with the deep learning models (i.e., ANN and ANFIS) was employed to enhance the performance of the water turbidity modeling. The results showed that deep learning techniques in temporal modeling of water turbidity have good accuracy and can be used with reasonable confidence. Also, data denoising increases the accuracy of deep learning methods in estimating the amount of water turbidity. ANFIS method is more accurate in both calibration and validation modes as well as in noisy and denoised conditions. Based on the results, data denoising in the ANN method has a more significant impact than in the ANFIS technique. For example, in Comb. 5, which is the best case, the improvement rate of the results in the ANN is 12% and in the ANFIS method is 4%. This could be due to the fuzzy system in handling uncertainties in the model.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"52 ","pages":"Pages 26-37"},"PeriodicalIF":2.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138991284","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":"Combining topography and reflectance indices for better surface water detection","authors":"Yuanming Hu,&nbsp;Jisoo Lee,&nbsp;Kyungrock Paik","doi":"10.1016/j.jher.2024.01.001","DOIUrl":"10.1016/j.jher.2024.01.001","url":null,"abstract":"<div><p>Since the Normalized Difference Water Index (NDWI) was proposed, water indices have served as useful tools for surface water detection. However, existing water indices are highly influenced by atmospheric and other environmental conditions and suffer from limited performance, especially in urban areas. At the core of the limitation is the sole dependency on the spectral distribution of reflectance signals. To overcome this, we propose to utilize topographic data as additional information for better water detection. Accordingly, the new index, namely Combined Water Index (CWI), is developed as the product of the topographic index and the reflectance-based index. These two indices excellently compensate each other: the former is free from noise issues but invariant over time while the latter can capture temporal dynamics of waterbody extents. The CWI is applied to four study areas of different development levels (natural, medium-sized cities, and megalopolis) in the Han River basin, South Korea. The water detection results of the CWI is promising, particularly in the heavily developed urban setting, demonstrated through visual images as well as various statistical measures.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"52 ","pages":"Pages 38-49"},"PeriodicalIF":2.8,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139411992","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":"Evaluation of collar efficiency to prevent scouring around cylindrical bridge piers under live bed condition","authors":"Mohammad Mashahir ,&nbsp;Amir Reza Zarrati ,&nbsp;Mojtaba Karimaei Tabarestani","doi":"10.1016/j.jher.2023.12.001","DOIUrl":"10.1016/j.jher.2023.12.001","url":null,"abstract":"<div><p>The present study was carried out to experimentally investigate the effect of single and double collar on development of local scouring around cylindrical bridge piers under live-bed condition. The single collar with diameter of 3 times the pier diameter placed on the streambed level and double collars one on the streambed level and one on a lower elevation were used. Tests were conducted with different flow intensities equal to 1.4, 2.0, 2.4, 2.8 and 4.0 where flow intensity is defined as the ratio of bed shear velocity to shear velocity of bed material at threshold of motion. One experiment was also carried out with flow intensity of 4.7 at which dunes were washed out and transition flow regime prevailed. The duration of the experiments was long enough to assure complete dune formations and multiple traverses of dunes through the pier location. Results showed that the scour depth fluctuated between a maximum and a minimum value due to the bed features migration. A graph was developed to show the efficiency of single and double collars at different positions and under different flow intensities. With two collars in place, the mean and maximum scour depths at the highest flow intensity, reduced by about 53% and 35% respectively. Efficiency of collar was better in lower flow intensities. Finally, based on the present results, a design table is presented for the elevation of the lower collar based on the flow intensity.</p></div>","PeriodicalId":49303,"journal":{"name":"Journal of Hydro-environment Research","volume":"52 ","pages":"Pages 17-25"},"PeriodicalIF":2.8,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138517795","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}