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Response of bedload transport, submarine topography, and dune internal structures to typhoon processes off Dongfang coast in the Beibu Gulf 认领 引用 被引量：3
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作者 MA Xiaochuan YAN Jun +1 位作者 FAN Fengxin YAO Ping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第4期27-40,共14页
Bedload sediment transport was estimated by the SEDTRANS96 model based on three-day hydrodynamics data obtained off the Dongfang coast in the Beibu Gulf during Typhoon Ketsana in September 2009. Bed- forms on the sea ... Bedload sediment transport was estimated by the SEDTRANS96 model based on three-day hydrodynamics data obtained off the Dongfang coast in the Beibu Gulf during Typhoon Ketsana in September 2009. Bed- forms on the sea floor off the Dongfang coast and internal structures of a typical dune were interpreted to evaluate storm influences on individual dunes and the dune field. Results indicated that flow forcings and related bedload transport were both strengthened significantly due to Typhoon Ketsana. The measurements and modeling results, which mainly included three different stages, presented noticeable phasic variation. The three stages were dominated by tidal current （Period I）, tidal current combined with wind-induced waves （Period II）, and swells combined with tidal current and seaward flows （Period III）. This phasic varia- tion could be a common trait of hydrodynamics due to typhoons moving westwardly to the south of Hainan Island and Beibu Gulf in South China Sea. Results indicated that the maximum bedioad transport rate for every burst in Period III was almost 100 times larger than that in Period I and was ten times larger than that in Period II. However, the short-term increase in bedload transport induced by storms like Ketsana did not change the long-term evolution of dune morphology. Evidence was given by the internal structures of a typical dune, which revealed renewed modification under subsequent moderate conditions after storm ero- sion. Instead, storms may influence at different scales and regional allocation of sand dunes in some large areas because changes of the sea floor in large scales can hardly be recovered. More surveys during and after storm passage are also needed to document the level of positive contribution to forward migration. 展开更多
关键词 typhoon bedload transport sand dune internal structure Beibu Gulf
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Influence of bed surface structure on bedload transport in mountain rivers 认领 引用 被引量：3
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作者 Xingnian Liu Hui Cao +3 位作者 Weiming Wu Ming Luo Lu Wang Chao Liu 《River》 2023年第3期350-358,共9页
Mountain rivers are characterized by wide grain size distributions and complex bed surface structures,which significantly affect bedload transport.Owing to the lack of a clear understanding of the quantitative influen... Mountain rivers are characterized by wide grain size distributions and complex bed surface structures,which significantly affect bedload transport.Owing to the lack of a clear understanding of the quantitative influence of the bed surface structure on the bedload transport rate,existing methods for estimating the bedload transport rate in mountain rivers produce large errors.Based on theoretical analysis andflume experiments,this study reveals the influence of bed surface structure on nonuniform bedload transport and proposes a method for estimating bedload transport rate considering the quantitative influence of bed surface structure.Thefindings of the present study provide theoretical methodological support for predicting the sediment transport and bed evolution in mountain rivers. 展开更多
关键词 bed surface structure bedload transport mountain rivers nonuniform sediment
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Development and installation of bedload monitoring systems with submerged load cells 认领 引用
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作者 Ken GOTO Takahiro ITOH +3 位作者 Takahiko NAGAYAMA Rei UTSUNOMIYA Daizo TSUTSUMI Takahisa MIZUYAMA 《Journal of Mountain Science》 SCIE CSCD 2016年第2期369-376,共8页
Bedload governs riverbed channel variations and morphology, it is necessary to determine bedload discharge through an arbitrary cross section in a mountain fiver. A new system with submerged load cells has been develo... Bedload governs riverbed channel variations and morphology, it is necessary to determine bedload discharge through an arbitrary cross section in a mountain fiver. A new system with submerged load cells has been developed to directly measure bedload discharge. The system consists of： （1） an iron box which is 1 m long, 0.5 m wide and 0.1 m in depth, （2） two submerged load cells 0.7 m apart, （3） a pressure sensor and, （4） an electromagnetic velocity meter. This system has been designed to exclude the effect of the hydraulic pressure of water on direct measurements of bedload particle weight. Initial tests in a laboratory were conducted to examine the accuracy of measurements with the system under aerial conditions. The system has been installed in the supercritical flume in Ashi-arai-dani River of the Hodaka Sedimentation Observatory of the Disaster Prevention Research Institute （DPRI） of Kyoto University to obtain bedload discharge under natural conditions. Flume tests were conducted in this channel by artificial supply of uniform sediment particles of several grain sizes. The average velocity of the sediment particles near the bed was estimated using cross-correlation functions for weight waves obtained by the two load cells, Bedload discharge calculations were based on time integration of the product of sediment velocity and sediment weight obtained by the two load cells. This study clarifies the reasons why bedload measurements are difficult, and provides some solutions using the monitoring systems with submerged load cells through the field measurements. Additionally, the applicability of bedload measurement with the submerged load cells is explained based on experimental artificial sediment supply data. 展开更多
关键词 Bedload Submerged load cell Flume tests
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Effect of upward seepage on bedload transport rate 认领 引用
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作者 Xiao-xie LIU Yee-Meng CHIEW 《Water Science and Engineering》 EI CAS CSCD 2014年第2期208-217,共10页
The paper presents an investigation of injection effects on the bedload transport rate. According to dimensional analysis, two dimensionless groups, an Einstein＇s parameter group and a modified densimetric Froude num... The paper presents an investigation of injection effects on the bedload transport rate. According to dimensional analysis, two dimensionless groups, an Einstein＇s parameter group and a modified densimetric Froude number group, were chosen to examine how injection affects the bedload transport rate. Experimental studies were conducted in an open-channel flume with an upward seepage zone. The sediment particles used for the test were 0.9 mm in diameter. The experimental results show that an increase in the injection velocity causes a reduction in the shear velocity excess, which is defined as the difference between the shear and critical shear velocities, leading to a reduction in the bedload transport rate. The equation for predicting the bedload transport rate in the presence of upward seepage was derived empirically. The proposed prediction method is suitable for engineering practice, since it only requires the undisturbed flow condition, properties of sediment particles, and the injection velocity. 展开更多
关键词 upward seepage bedload transport rate shear velocity shear stress open-channel flow
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Influence of river vegetation on sediment transport and erosion mitigation:A review 认领 引用
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作者 Mohd Nadim Ahmed Berlin Mohanadhas 《Research in Cold and Arid Regions》 CAS CSCD 2026年第2期101-105,共5页
Natural river systems are essential for conveying water,sediments,and organic material from upstream catchments to downstream reaches.One of the key processes influencing channel morphology is bedload transport,define... Natural river systems are essential for conveying water,sediments,and organic material from upstream catchments to downstream reaches.One of the key processes influencing channel morphology is bedload transport,defined by the movement of coarse sediments on the channel bed.Vegetation within channels significantly modifies bedload dynamics,offering both obstructive and supportive effects on sediment transport processes.This review synthesizes current understanding of how instream vegetation governs sediment mobility and erosion control by integrating insights from hydraulic,geomorphic,and ecological perspectives.The analysis highlights how vegetation influences flow structure and shear stress distribution,and examines its role in enhancing sediment capture,deposition,and stabilization.The review also considers how vegetation shapes channel morphology and supports bar formation.In addition,it explores the feedback loops connecting vegetation,hydraulic forces,and bedload transport.Finally,key research gaps are identified,with suggested future directions to improve understanding of vegetation and bedload interactions within natural river channels. 展开更多
关键词 Channel bank stability Riparian vegetation interactions Sediment stabilization strategies Bedload dynamics
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Incipient motion of non-uniform coarse grain of bedload considering the impact of two-way exposure 认领 引用 被引量：5
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作者 BAI YuChuan WANG Xin CAO YongGang 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第8期1896-1905,共10页
The incipient motion of bedload is due to the interaction between the flow and sediment.It is stochastically correlated with the flow structure,the sediment gradation and the arrangement of grains on the bed surface.T... The incipient motion of bedload is due to the interaction between the flow and sediment.It is stochastically correlated with the flow structure,the sediment gradation and the arrangement of grains on the bed surface.The random position of the sediment on bed can be represented by a hiding factor or an exposure degree.Based on the numerical simulation of the disturbed flow in the interstice of grains,the influence of the two-way exposure degree(the vertical exposure degree and the longitudinal exposure degree) on the coarse grain incipient motion was investigated in this work.Results show that the exposure degree varies with the position of the sediment on the bed,which influences the flow structure around the particle and the incipient motion.In this paper,the major research achievements on this phenomenon include:Firstly,a mathematical model is established for the rolling-pattern incipient motion of the coarse grain under a critical state of moment balance.The influence of the partial disturbed flow is considered.Secondly,the two-way relative-exposure-degree probability distribution functions are developed to reflect the influence of the disturbed flow and the random arrangement of sediments.Thirdly,a formula to calculate the incipient velocity is presented based on the above results,which considers the impact of the two-way exposure degree of sediment particles. 展开更多
关键词 coarse grain of bedload exposure degree rolling incipient model moment equilibrium incipient velocity
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Single and joint effects of HHCB and cadmium on zebrafish (Danio rerio) in feculent water containing bedloads 认领 引用 被引量：5
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作者 Lei ZHANG Jing AN Qixing ZHOU 《Frontiers of Environmental Science & Engineering》 SCIE CSCD 2012年第3期360-372,共13页
As an important type of emerging pollutants, ecological toxicity and risk of artificial musks are increasingly concerned. Thus, single and joint toxic effects of 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta... As an important type of emerging pollutants, ecological toxicity and risk of artificial musks are increasingly concerned. Thus, single and joint toxic effects of 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta-gamma-2-benzopyran （HHCB） as one of the most widely applied artificial musks and cadmium （Cd） as an toxic metal on zebrafish （Danio rerio） were investigated by the exposure of zebrafish to various concentrations of HHCB or/and Cd in feculent water containing bedloads. The results indicated that the joint effect of HHCB and Cd changed during different exposure times within 120 h. The index of the antioxidant enzyme system including superoxide dismutase （SOD） and perox- idase （POD）, and malondialdehyde （MDA） were sensitive and induced in the zebrafish stressed by Cd, and content of soluble protein （SP） was sensitive to HHCB and could be used as a biomarker for HHCB. Joint effects on antioxidant enzymes depended more on the effect of single Cd in the first one or two days. However, in the rest exposure days, the effect of HHCB began to dominate in the joint effect during the exposure process. 展开更多
关键词 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyran （HHCB） cadmium （Cd） antioxidant biomarker feculent water containing bedloads
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Study of bedload transport in backwater flow 认领 引用 被引量：1
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作者 金中武 卢金友 吴华莉 《Journal of Hydrodynamics》 SCIE EI CSCD 2016年第1期153-161,共9页
This paper studies the flow structure and the bedload transport regime in backwater flows, to provide a theoretical support for solving the sediment transport and bed scour problems in rivers or reservoirs with backwa... This paper studies the flow structure and the bedload transport regime in backwater flows, to provide a theoretical support for solving the sediment transport and bed scour problems in rivers or reservoirs with backwater. The bedload transport rates under different conditions are analyzed first on the basis of theoretical analysis, measurement comparison and flume experiment, and it is pointed out that the existing formulas for the bedload transport rate are not applicable for the bedload transport rate in backwater flows. Next, the flow structure in a non-uniform flow is observed by flume experiments, and by introducing the backwater degree index, the quantitative relation between the relative bed shear stress and the backwater degree is obtained. Finally, the formula for the bedload transport rate applicable for the reservoir channel segment with backwater flows is obtained through measurements and flume experiments. 展开更多
关键词 backwater flow bedload transport flume experiment formula for bedload transport rate
山区河流推移质簇群形成及演变特征试验研究 认领 引用
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作者 肖毅 尹思琪 +1 位作者 邓敬宏 刘洁 《泥沙研究》 CAS CSCD 北大核心 2026年第1期16-22,共7页
推移质簇群是山区河流床面微地貌结构的重要组成部分,对泥沙输移、河床阻力及河道地形塑造具有显著影响。通过连续水流变化条件下的均匀推移质簇群演化概化试验,分析了簇群演变过程与水流强度响应关系及簇群形态的统计特征。试验结果表... 推移质簇群是山区河流床面微地貌结构的重要组成部分,对泥沙输移、河床阻力及河道地形塑造具有显著影响。通过连续水流变化条件下的均匀推移质簇群演化概化试验,分析了簇群演变过程与水流强度响应关系及簇群形态的统计特征。试验结果表明,簇群形成数量的概率密度分布与水流强度关系密切,不同床面布置形式的簇群演变过程特征参数存在差异。矩形密排床面的簇群形成、稳定、崩解阶段存在明确的水流强度阈值,通过对颗粒与床面接触面受力分析可知,梅花形密排床面的颗粒起动水流拖曳力为矩形密排床面的73.82%,因此相同水流条件下梅花形密排床面的簇群运动更剧烈,较难形成稳定阶段。研究成果为理解推移质簇群演变机理提供了理论基础,也为山区河流微地貌变化与水流条件响应量化关系研究提供了参考。 展开更多
关键词 推移质运动 簇群演变 床面布置形式 水槽试验 山区河流
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Prediction of bedload transport inside vegetation canopies with natural morphology 认领 引用 被引量：3
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作者 Li He Yu-qi Shan +3 位作者 Chao Liu Hui Cao Xing-nian Liu Yakun Guo 《Journal of Hydrodynamics》 SCIE EI CSCD 2024年第3期556-569,共14页
Due to vegetation drag and vegetation-generated turbulence,bedload transport in vegetated channels is more complicated than that in nonvegetated channels.It is challenging to obtain accurate predictions of bedload tra... Due to vegetation drag and vegetation-generated turbulence,bedload transport in vegetated channels is more complicated than that in nonvegetated channels.It is challenging to obtain accurate predictions of bedload transport in vegetated channels.Previous studies generally used rigid circular cylinders to simulate vegetation,and the impact of plant morphology on bedload transport was typically ignored;these methods deviate from natural scenarios,resulting in prediction errors in transport rates of more than an order of magnitude.This study measured bedload transport rates inside P.australis,A.calamus and T.latifolia canopies and in arrays of rigid cylinders for comparison.The impact of plant morphology on bedload transport in vegetated channels was examined.Inside the canopies of natural morphology,the primary factor driving bedload transport is the near-bed turbulent kinetic energy(TKE),which consists of both bed-generated and vegetation-generated turbulence.A method was proposed to predict the near-bed TKE inside canopies with natural morphology.For the same solid volume fraction of plants,the transport rate inside canopies with a natural morphology is greater than or equal to that within an array of rigid cylinders,depending on the plant shape.This finding indicates that plant morphology has a significant impact on transport rates in vegetated regions and cannot be ignored,which is typical in practice.Four classic bedload transport equations(the Meyer-Peter-Müller,Einstein,Engelund and Dou equations),which are suitable for bare channels(no vegetation),were modified in terms of the near-bed TKE.The predicted near-bed TKE was inserted into these four equations to predict the transport rate in canopies with natural morphology.A comparison of the predictions indicated that the Meyer-Peter-Müller equation had the highest accuracy in predicting the transport rate in vegetated landscapes. 展开更多
关键词 Vegetated landscapes turbulent kinetic energy(TKE) bedload transport plant morphology predictive methods
水库变动回水区推移质运动数值模拟研究 认领 引用
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作者 郭勇邦 王森 +2 位作者 李坤芳 王茂旭 罗铭 《水电能源科学》 北大核心 2026年第5期71-75,58,共5页
水库变动回水区是推移质运动与河床冲淤变化最为集中的关键河段,其输移与淤积过程受库水位调度与洪水过程的共同影响。为此,以紫坪铺水库龙溪河库尾段变动回水区为例,在物理模型试验成果基础上,建立二维水沙耦合数值模型,设置不同库水... 水库变动回水区是推移质运动与河床冲淤变化最为集中的关键河段,其输移与淤积过程受库水位调度与洪水过程的共同影响。为此,以紫坪铺水库龙溪河库尾段变动回水区为例,在物理模型试验成果基础上,建立二维水沙耦合数值模型,设置不同库水位与不同频率洪水组合工况,对推移质淤积体的平面形态演化及典型横断面冲淤特征进行对比分析。结果表明,在相同来水来沙条件下,库水位变化通过调整回水顶托范围及急缓流转换位置,显著影响推移质淤积体的形成部位、纵向展布范围及最大淤积厚度;与较高水位工况相比,降低库水位可增强回水区水动力条件,使推移质淤积体整体向下游迁移,并由集中型向分散型转变,最大淤积厚度由6.1 m减小至2.2 m。在库水位保持不变且来沙总量一致的条件下,洪水频率由中等洪水增大至大洪水,对推移质淤积宏观平面格局的影响相对有限,主要表现为局部冲淤幅度及纵向再分配特征的调整。 展开更多
关键词 水库变动回水区 频率洪水 库水位 推移质运动 二维数值模拟
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植被影响下的弯曲分汊河道水沙特性 认领 引用 被引量：4
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作者 王森 李坤芳 +2 位作者 刘兴年 黄尔 罗铭 《工程科学与技术》 EI CAS CSCD 北大核心 2025年第1期29-36,共8页
弯曲分汊河道由于其特殊的地形和复杂的水沙运动特性,对河势稳定、防洪、航运及沿岸经济发展都有着深远的影响。植被作为河流生态系统的组成部分,对河床演变形态具有重要影响,且植被往往分布在弯曲分汊河道的凸岸淤积段或洲滩。本文基... 弯曲分汊河道由于其特殊的地形和复杂的水沙运动特性,对河势稳定、防洪、航运及沿岸经济发展都有着深远的影响。植被作为河流生态系统的组成部分,对河床演变形态具有重要影响,且植被往往分布在弯曲分汊河道的凸岸淤积段或洲滩。本文基于物理模型试验,开展系列不同来流及不同植被密度影响下的弯曲分汊河道动床非恒定流概化试验,分析植被影响下弯曲分汊河道冲刷与再造过程中的水流和泥沙的输移特性。结果表明:非恒定过程条件下,左汊分流比受植被影响较为显著,且随着支汊植被密度的增加呈现增大的趋势;分流比对右汊有无植被布设较为敏感,但植被布设密度的大小对分流比影响较小。对于推移质输移,支汊植被的存在增大了弯曲分汊河段推移质的输沙率和输沙级配,随着右汊植被覆盖密度的增加,推移质输沙率峰值有所增大,同时推移质输沙波动亦增大,流量较大时波动性表现更为显著。汊道相互影响量化参数的变化表明弯曲分汊河道再造过程中汊道间的影响随着支汊植被密度的增加呈现出较大的增加幅度。研究成果一定程度上可为相关的河道整治、河流生态修复等提供理论支持。 展开更多
关键词 弯曲分汊河道 植被影响 水流特性 推移质输移 非恒定流
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黄河下游输沙需水量模拟预测研究 认领 引用 被引量：3
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作者 李琳琪 张红武 +3 位作者 傅旭东 侯琳 郭庆超 黄海 《水利学报》 EI CSCD 北大核心 2025年第8期1037-1048,共12页
黄河下游输沙需水量的合理预测对优化水沙调控、保障防洪安全及提升河道治理效果至关重要。本文引入带有平均含沙量分布系数a_*与非饱和系数f_S的非平衡输沙方程计算沿程含沙量变化,以河床综合稳定性指标作为河道整治工程的约束程度,构... 黄河下游输沙需水量的合理预测对优化水沙调控、保障防洪安全及提升河道治理效果至关重要。本文引入带有平均含沙量分布系数a_*与非饱和系数f_S的非平衡输沙方程计算沿程含沙量变化,以河床综合稳定性指标作为河道整治工程的约束程度,构建出黄河下游河段冲淤数值模型,并利用黄河下游实测水沙数据对模型进行验证。通过选取不同来水来沙条件的10组方案进行模拟,研究发现输沙需水量与来沙量呈正相关关系,在来沙量超过5亿t时,需水量增长趋缓。此外,河道整治程度的提高能够有效减少输沙需水量,例如,当河床综合稳定性指标Z_W由4提升至4.5时,相同来沙量下的需水量可降低约10%。进一步的模拟预测显示,黄河下游未来年输沙量在2亿~3亿t时,输沙需水量为100亿~155亿m3,且当前水资源配置基本能够满足输沙需求。本研究的成果可为黄河下游水沙调控及河道治理提供科学依据,并对高含沙河流的水沙调控研究亦具有重要的参考价值。 展开更多
关键词 输沙需水量 黄河下游 河床综合稳定性指标 数值模型 推移质输沙
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山区河流推移质输移高频声震信号监测研究进展 认领 引用 被引量：1
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作者 陈政 方卫华 +2 位作者 许少华 罗铭 何思明 《工程科学与技术》 EI CAS CSCD 北大核心 2025年第6期1-17,共17页
对山区河流推移质输移过程的定量预测是开展山区水沙灾害评估及水利工程建设的关键所在。然而,陡急山区河推移质输沙率显示出强烈的时空脉动性。受限于当前对推移质输移过程的测量手段,现有对推移质输移过程的认识仍十分有限。针对传统... 对山区河流推移质输移过程的定量预测是开展山区水沙灾害评估及水利工程建设的关键所在。然而,陡急山区河推移质输沙率显示出强烈的时空脉动性。受限于当前对推移质输移过程的测量手段,现有对推移质输移过程的认识仍十分有限。针对传统直接测量方法采样效率低且可达性差,难以实现对推移质输沙率长期、连续且精细化测定的技术问题,系统论述基于高频声震信号的山区河流推移质输移监测技术研究进展,为下一步相关研究提供突破口。推移质输移过程诱发的高频声震信号为其运动规律研究及输沙参数反演提供新途径,通过构建不同类型的推移质声震监测系统为载体,监测和记录推移质碰撞声震能量,解析声震信号诱发机制,推演推移质输沙关键参数,最终完成对山区河流推移质全过程输沙通量的动态计算。山区河流推移质输移过程高频声震信号监测研究的关键问题和难点体现在以下4个方面:1)推移质多源声震监测系统的构建。全方位记录推移质碰撞、冲击河床所激发的高频声震信号。2)推移质输移声震信号特征识别与计算。通过对监测震动信号进行降噪、卷积变换和特征分析,获取信号波包、脉冲响应、振幅分布、特征频率及功率谱密度等重要参数。3)推移质高频声震信号解译算法。实现推移质震源空间定位、信号震源物理模型构建及信号传播与衰减模型的构建。4)推移质输沙物理参数精细化反演。通过监测震动信号结合所构建标定模型反演计算推移质分组粒径、输移速度、运动模式及输沙率等关键参数。针对上述4个方面的内容,结合最新研究成果,对高频声震信号在陡峭山区河流推移质输移过程监测方面的研究进展进行总结和讨论,并对目前研究领域面临的几个问题做出建议:构建基于多传感元件普适性更强的声震联合监测系统,开展更为精细的推移输声震信震源机制研究,系统性建立各信号响应指标与输沙参数指标的数据库,可基于机器学习方法实现更为高效的推移质输沙过程反演。本文可为完善山区河流推移质输移监测体系、水沙灾害定量评估、山区水利工程建设与长期运营等方面提供科学依据。 展开更多
关键词 山区河流 推移质 声震信号 监测系统 震源机制 输沙率
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基于深度学习的推移质颗粒识别优化算法研究 认领 引用
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作者 王浩 杨飞奇 +3 位作者 张磊 吴伟 谢皓南 赵琳 《工程科学与技术》 EI CAS CSCD 北大核心 2025年第4期138-149,共12页
推移质运动规律对河床演变具有重要影响,是河流动力学研究的重点和难点。本文开展中低水流条件下的推移质平衡输沙试验,将灰度相减方法和深度学习方法相结合,旨在提出一种优化的推移质运动颗粒识别算法,并在此基础上应用粒子跟踪测速技... 推移质运动规律对河床演变具有重要影响,是河流动力学研究的重点和难点。本文开展中低水流条件下的推移质平衡输沙试验,将灰度相减方法和深度学习方法相结合,旨在提出一种优化的推移质运动颗粒识别算法,并在此基础上应用粒子跟踪测速技术(PTV)和卡尔曼滤波算法计算推移质颗粒运动轨迹,从而建立紊流相干结构与颗粒运动强度关系。为清晰捕捉运动距离较小颗粒,对YOLOv5(you only look once)目标检测模型网络结构进行卷积块改进、增加注意力机制和优化损失函数处理,以增强其在推移质颗粒识别任务中对极小目标的检测能力。结果表明:1)灰度相减方法可识别运动距离较大的颗粒,改进YOLOv5模型则能够更好识别运动距离较小的颗粒,通过合并优化两种方法,在本文设置的试验工况下可更准确识别推移质运动颗粒和运动轨迹;2)中低水流强度条件下,推移质泥沙颗粒运动强度受紊流相干结构影响沿水槽横向方向呈现间隔条带结构,并且随着水流强度增加,条带结构逐渐由密集变得稀疏,其宽度也由窄转宽,当水流强度继续增大时紊动掺混剧烈,条带结构遭到破坏逐渐消失;3)总体看来:泥沙颗粒运动多集中在水槽中间区域,边壁处运动较少,沙条带结构呈现中间宽两边窄的空间分布特征,表明条带结构是受紊流大尺度相干结构的影响而形成,而非二次流结构。 展开更多
关键词 推移质 灰度相减 YOLOv5 颗粒运动轨迹 条带结构
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山区河流推移质泥沙监测技术研究进展 认领 引用
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作者 罗铭 刘兴年 +3 位作者 彭万兵 吴小康 何逸敏 黄尔 《工程科学与技术》 EI CAS CSCD 北大核心 2025年第1期11-20,共10页
受推移质监测技术的限制,高精度瞬时监测和分析天然山区河流的推移质输移特征变化存在困难,形成技术瓶颈。全球气候变化导致河流水沙变化巨大,加剧了中国的山区河流保护与治理事业的挑战。本文按照直接监测和间接监测分类对近年国内外... 受推移质监测技术的限制,高精度瞬时监测和分析天然山区河流的推移质输移特征变化存在困难,形成技术瓶颈。全球气候变化导致河流水沙变化巨大,加剧了中国的山区河流保护与治理事业的挑战。本文按照直接监测和间接监测分类对近年国内外推移质监测技术研究进展进行了全面整理。直接监测法包括了器测法和坑测法,其中器测法发展较为成熟,但直接监测法在高洪条件下的可操作性及安全性问题仍然突出。间接监测法可连续、长期地记录包含河床变化、推移质输移等信号,主要分为主动监测法和被动监测法,其中被动监测法又分为接触与非接触式,包括了推移质击板/柱/管、地震检波器、水听器等。但间接监测法传感器所记录的信号通常非常复杂,对信号的有效解译及量化标定关系成为该类研究的热点及难点。据此,本文指出了原型观测站点的建设、多源信号监测技术的融合、流域推移质泥沙监测装备体系的构建是未来研究的重点和亟待解决的科技问题。 展开更多
关键词 山区河流 推移质泥沙 监测技术 研究进展
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基于分布式水文模型的阿伦河流域输沙模拟 认领 引用
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作者 黄金柏 王庆明 +1 位作者 王斌 温佳伟 《泥沙研究》 CAS CSCD 北大核心 2025年第5期25-33,共9页
为揭示东北寒区中尺度流域输沙特性,选取阿伦河流域为研究区,基于自研发的物理性分布式水文模型,耦合悬移质和推移质计算模块,构建耦合输沙的降雨-径流过程分布式水文模型,通过对控制案例计算结果与含沙量采样粒径级配的比较,检验模型... 为揭示东北寒区中尺度流域输沙特性,选取阿伦河流域为研究区,基于自研发的物理性分布式水文模型,耦合悬移质和推移质计算模块,构建耦合输沙的降雨-径流过程分布式水文模型,通过对控制案例计算结果与含沙量采样粒径级配的比较,检验模型的实用性。研究区2016年输沙过程计算结果表明:模拟结果的均方根误差(RMSE)小于0.1,输沙过程受流量过程的支配;输沙主要为悬移质,最大洪峰期间,研究区出口断面悬移质占输沙量的90%以上,常流条件下,悬移质占输沙量的80%以上;冬季各月输沙量对年输沙的贡献率小于0.15%;6月、7月、9月和10月的月输沙量对年输沙的贡献率大于15%。研究结果为东北寒区水沙耦合运动过程研究提供基础数据。 展开更多
关键词 阿伦河流域 物理性分布式水文模型 降雨-径流 泥沙输移 推移质 悬移质
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基于分类梯度提升算法的推移质输沙率计算 认领 引用
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作者 王言昕 江雨润 +2 位作者 吴小康 罗铭 黄尔 《水电能源科学》 北大核心 2025年第1期39-42,121,共4页
计算宽级配推移质运动是河流泥沙学科的难点之一。为探寻分类梯度提升算法在预测推移质输沙率方面的效果,筛选了3 060组天然河道输沙数据,将其划分为单一流域和综合流域两组,以此获取算法在这两种情况下的预测结果,并利用3种传统公式进... 计算宽级配推移质运动是河流泥沙学科的难点之一。为探寻分类梯度提升算法在预测推移质输沙率方面的效果,筛选了3 060组天然河道输沙数据,将其划分为单一流域和综合流域两组,以此获取算法在这两种情况下的预测结果,并利用3种传统公式进行对比,最后对单点进行多次重复调参验证调参次数对于算法预测性能的影响。结果表明,分类梯度提升算法对单一流域的预测效果优于综合流域;增加训练集和测试集的划分次数能够减轻划分方式带来的影响;多次重复调参可提高算法的预测性能;分类梯度提升算法相较于传统输沙率公式效果更好。 展开更多
关键词 分类梯度提升算法 推移质输沙率 机器学习 野外数据
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不同床面布置型式推移质颗粒运动特性试验研究 认领 引用
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作者 吴建民 肖毅 邓敬宏 《水道港口》 2025年第6期861-867,895,共7页
推移质运动速度是研究推移质运动规律的最基本要素之一,其受水流强度、床面结构、泥沙补给等多方面影响,显著影响着河道输沙率与河床演变过程。基于当量粗糙高度条件下两种床面布置的推移质颗粒运动概化试验,分析了颗粒运动速度的时均... 推移质运动速度是研究推移质运动规律的最基本要素之一,其受水流强度、床面结构、泥沙补给等多方面影响,显著影响着河道输沙率与河床演变过程。基于当量粗糙高度条件下两种床面布置的推移质颗粒运动概化试验,分析了颗粒运动速度的时均特征和概率密度分布。试验结果表明:在保证颗粒连续运动的水流条件下,矩形密排床面上颗粒主要沿流向运动,速度表现为“加速-减速-加速”的周期特征;梅花形密排床面上颗粒展向摆动幅度和频率明显增大,其他运动特征与矩形密排床面情况基本一致。流向速度概率密度分布呈Gamma分布;展向速度概率密度分布服从正态分布;梅花形密排床面展向速度范围更分散,表明当量粗糙高度条件下不同床面布置型式对颗粒运动速度大小产生一定影响,但颗粒运动速度的概率统计特征趋向一致。 展开更多
关键词 推移质运动 床面型式 概率密度 水流强度 粗糙度 流速
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Fluvial Transport of Large Boulders 认领 引用
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作者 Robert E.Criss William E.Winston G.Robert Osburn 《Journal of Earth Science》 SCIE CAS CSCD 2024年第6期2045-2049,共5页
Fast water can cause extraordinary bedload transport.Of the record floods considered here,the Jul.26,2022 urban flash flood on the upper River des Peres,St.Louis,Missouri provides particularly well-constrained data on... Fast water can cause extraordinary bedload transport.Of the record floods considered here,the Jul.26,2022 urban flash flood on the upper River des Peres,St.Louis,Missouri provides particularly well-constrained data on flow conditions associated with large block movement.Field measurements and a detailed lidar survey show that concrete slabs as large as 3.0×2.5×0.33 m3were moved from the open channel to reside 215 to 450 m inside a 6.5 m-diameter drainage tunnel,some to become part of a 10-m long imbricated pile.Peak flows of 160 m3/s were recorded at a gauging station located only 1.6 km upstream of the tunnel entrance,which provides a good estimate of 4.2 m/s for the peak flow velocity in the tunnel.Available observational data and a new theoretical analysis show that the radius of large boulders that can be moved by flowing water is directly proportional to the velocity head. 展开更多
关键词 fluvial transport imbrication floods lidar survey bedload urban flash flood hydrogeology
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