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Experimental Study of Sediment Incipience Under Complex Flows 预览
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作者 LIU Chunrong DENG Liying +1 位作者 HUANG Zhenhua HUHE Aode 《天津大学学报:英文版》 EI CAS 2008年第4期 300-306,共7页
在传递向后面对的步的流动下面的沉积开始被学习。一系列实验被进行测量向后面对的步下游地搜索深度,沉积开始的概率,和即时流动速度地。即时流动速度领域被使用粒子图象 Velocimetry (PIV ) 测量,并且为决定沉积开始的概率处理方法... 在传递向后面对的步的流动下面的沉积开始被学习。一系列实验被进行测量向后面对的步下游地搜索深度,沉积开始的概率,和即时流动速度地。即时流动速度领域被使用粒子图象 Velocimetry (PIV ) 测量,并且为决定沉积开始的概率处理方法的一幅图象被采用分析试验性的数据。试验性的结果证明沉积开始的概率在附件点附近是最高的,尽管近墙的即时流动速度和雷纳兹压力向后面对的步进一步下游地两个都是高得多的。可能的机制在附件点附近为沉积开始被讨论。 展开更多
关键词 土砂 混合 泥沙运动 粒子图像速度计
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Scour and Scour Countermeasures at Bridge Sites 预览
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作者 CHIEW Yee-Meng 《天津大学学报:英文版》 EI CAS 2008年第4期 289-295,共7页
这篇论文检验在桥墩和桥墩搜索并且搜索反措施。桥墩搜索迄今为止比它因为一个泛滥平原的存在的可能性,与墩联系的对应物更复杂。尽管有这,机制在墩和桥墩搜索是很类似的;而且,失败机制与 armoring 和改变流动的反措施联系了不是很... 这篇论文检验在桥墩和桥墩搜索并且搜索反措施。桥墩搜索迄今为止比它因为一个泛滥平原的存在的可能性,与墩联系的对应物更复杂。尽管有这,机制在墩和桥墩搜索是很类似的;而且,失败机制与 armoring 和改变流动的反措施联系了不是很不同的。在有一个泛滥平原的河里,桥墩搜索成为更多建筑群。在桥墩在在哪儿或在附近结束的情况中到泛滥平原,它能开始河岸侵蚀,它清楚地是从惯例书是相当不同的一个重要侵蚀问题没有一个泛滥平原或墩,在河里在也搜索一个桥墩。为这个原因,桥墩搜索当码头搜索在自然是更通用的时,能很地点特定。到这个目的,识别桥墩的类型的能力搜索那可以在一条特别隧道形成仔细与一个工程师建议设备为的能力有关有效搜索反措施。由在在过去几十年把在用作墩或桥墩反措施上总结研究努力,这篇论文在逮捕加亮在的缺乏墩搜索。到这个目的,不同失败机制被识别。他们是砍失败,扬的失败,边失败,导致 bedform 的失败和床降级导致了失败。每失败机制单身地装或,更多半,联合引起在层的最终的故障。尽管它足够地被设计对,在层对另外的失败机制脆弱的学习表演砍失败,在逮捕使它变为无效搜索。 展开更多
关键词 桥梁 桥礅冲刷 工程 冲刷对策 土砂
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SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY 预览 被引量:9
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作者 CHEN Bin WANG Kai 《水动力学研究与进展:英文版》 SCIE EI CSCD 2008年第3期 373-381,共9页
Based on the Estuarine,Coastal and Ocean Modeling System with Sediments(ECOMSED) model,a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East China Sea.... Based on the Estuarine,Coastal and Ocean Modeling System with Sediments(ECOMSED) model,a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East China Sea.The hydrodynamic module was driven by tide and wind.Sediment module included sediment resuspension,transport and deposition of cohesive and non-cohesive sediment.The settling of cohesive sediment in the water column was modeled as a function of aggregation(flocculation) and deposition.The numerical results were compared with observation data for August,2006.It shows that the sediment concentration reduces gradually from the seashore to the offshore area.Numerical results of concentration time series in the observation stations show two peaks and two valleys,according with the observation data.It is mainly affected by tidal current.The suspended sediment concentration is related to the tidal current during a tidal cycle,and the maximum concentration appears 1h-4h after the current maximum velocity has reached. 展开更多
关键词 长江河口 沉积物浓度 土砂 河口动力学
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Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, China 预览 被引量:4
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作者 J.H. ZHANG Z.A. SU G.C. LIU 《山地科学学报:英文版》 SCIE CSCD 2008年第3期 241-248,共8页
在四川盆的多山的区域的土壤侵蚀是对持续庄稼生产和健全生态系统的一颗严肃的担心。一个 3 年的实验用流量情节的方法被进行在 Jianyang 县在多山的区域在土壤和斜坡地的水保存上在农田系统检验阶田耕作和 agroforestry 的效果,四川... 在四川盆的多山的区域的土壤侵蚀是对持续庄稼生产和健全生态系统的一颗严肃的担心。一个 3 年的实验用流量情节的方法被进行在 Jianyang 县在多山的区域在土壤和斜坡地的水保存上在农田系统检验阶田耕作和 agroforestry 的效果,四川省,西南的中国。力量功能(Y = 斧子 <SUP > b </SUP>) 能统计上描述在水流量(Y) 和降雨(X) 之间的关系。为与庄稼(阴谋 2 )泼出平台的处理的回归方程为与草和树(阴谋 1 )泼出平台的处理与那显著地不同并且在上面常规--并且关于方程系数的下坡的庄稼系统(阴谋 3 ),当回归方程在阴谋 1 和阴谋 3 之间是类似的时。斜坡地的水流量数量和流量系数由 21.5 &#8764;41.0 % 和 27.5 &#8764; 增加了69.7 % 分别地,与那些相比泼出平台,显著地建议那 terracing 在这块地里减少了水流量。在泼出平台的情况中,水流量的更低的数量在比在与草和树泼出平台上与庄稼泼出平台上被观察。降雨分布的正常的年里的斜坡地上的沉积收益尤其是更高(34.41 &#8764; 331.67 % 和 37.06 &#8764; 403.44 % 为情节 1 和情节 2,分别地) 比那些在泼出平台上,暗示那阶田耕作也在土壤侵蚀在减小起一个重要作用。有庄稼的阶田耕作在栽培农田为土壤和水保存是显著地有效的,这被建议,当时常规实践起来 -- 并且下坡的耕作创造水流量和土壤沉积运输的高率。有草和果树的阶田耕作与庄稼比 terracing 在水流量显示出更少减小,它在 3 年的实验被观察。 展开更多
关键词 林粮间作 土砂 坡式梯田 水土
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Applications of GSTARS Computer Models for Solving River and Reservoir Sedimentation Problems 预览
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作者 YANG Chih Ted 《天津大学学报:英文版》 EI CAS 2008年第4期 235-247,共13页
GSTARS (为冲积的河模拟的概括沉积运输模型) 是当作者被那个机构雇用时,模型由开垦的美国局开发了的一系列计算机。溪流试管概念在允许我们独立地为每个溪流试管解决一个维的方程并且为河和水库获得水力的条件的半二维的变化沿着并且... GSTARS (为冲积的河模拟的概括沉积运输模型) 是当作者被那个机构雇用时,模型由开垦的美国局开发了的一系列计算机。溪流试管概念在允许我们独立地为每个溪流试管解决一个维的方程并且为河和水库获得水力的条件的半二维的变化沿着并且越过溪流试管的所有 GSTARS 模型被使用。沉积搬运,搜索,并且免职进程独立地沿着每个流试管被模仿给我们床几何学的一个半三维的变化。大多数沉积运输计算机模型假设那隧道宽度在模拟过程期间被给并且不能变化。GSTARS 模型把最小的溪流电源的理论用于最佳隧道宽度和隧道几何学的决心。隧道方面稳定性的概念,并且活跃,不活跃,并且 armoring 层在河和水库里为 scour 和免职过程的现实主义的长期的模拟和预言在所有 GSTARS 模型被使用。GSTARS 模型为解决大量河和水库沉积问题在许多国家被使用了。案例研究将被用来说明 GSTARS 计算机模型的应用程序。 展开更多
关键词 水库 土砂 计算机模型
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River Morphology and River Channel Changes 预览
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作者 CHANG Howard H 《天津大学学报:英文版》 EI CAS 2008年第4期 254-262,共9页
河形态学是对认识到关于河工程的任何努力必须基于包含的词法特征和对强加的变化的回答的合适的理解的科学家和工程师的大挑战的一个题目。在这篇论文,河形态学的概述从似地球形状的观点被给出。在范围包括了是政体概念,河隧道分类,... 河形态学是对认识到关于河工程的任何努力必须基于包含的词法特征和对强加的变化的回答的合适的理解的科学家和工程师的大挑战的一个题目。在这篇论文,河形态学的概述从似地球形状的观点被给出。在范围包括了是政体概念,河隧道分类,在河形态学的阀值,和河回答的似地球形状的分析。基于为流动和沉积的 hydraulics 的物理原则,运输处理的河形态学的分析途径也被介绍。分析的河形态学的应用程序被一个例子演示。当模特儿是现代技术在环境决定短期、长期的河隧道回答到任何变化。河的过程反应的物理基础必须在格式化一个数学模型被使用。数学模型 FLUVIAL-12 的简短介绍被描述。 展开更多
关键词 形态学 水道改变 土砂 类型 数学模型
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Non-Uniform Sediment Transport Downstream from Reservoir 预览 被引量:1
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作者 李义天 陈飞 《天津大学学报:英文版》 EI CAS 2008年第4期 263-270,共8页
The transport characters of non-uniform sediment before and after the reservoir operation are compared and analyzed. Field data from the Three Gorges Reservoir (TGR), Danjiangkou, and Sanmenxia reservoir indicate that... The transport characters of non-uniform sediment before and after the reservoir operation are compared and analyzed. Field data from the Three Gorges Reservoir (TGR), Danjiangkou, and Sanmenxia reservoir indicate that the transport character of coarse particle is various in different reaches. Before the reservoir operation, the dramatic decrease of the hydraulic condition in some reaches is the main reason to cause the coarse particle deposited. After the reservoir operation, almost all grain sized sediment may be eroded, when the reach is eroded seriously. However, the transport character of the coarse particle will be consistent with what it was before, when the reach is not eroded seriously. The deposition amount will be less than its pre-dam value, and it will tend to decrease with the time going on. Erosion of fine particle results from its unsaturation. Longdistance erosion downstream from reservoir is caused by shortage of the supply from riverbed, especially the shortage of fine particle. 展开更多
关键词 水库下游 土砂 沉淀物尺寸 水力学
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AN ANALYTICAL SOLUTION FOR CALCULATING THE INITIATION OF SEDIMENT MOTION 预览 被引量:2
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作者 Thomas LUCKNER Ulrich ZANKE 《国际泥沙研究:英文版》 SCIE 2007年第2期 87-102,共16页
This paper presents an analytical solution for calculating the initiation of sediment motion and the risk of river bed movement. It thus deals with a fundamental problem in sediment transport, for which no complete an... This paper presents an analytical solution for calculating the initiation of sediment motion and the risk of river bed movement. It thus deals with a fundamental problem in sediment transport, for which no complete analytical solution has yet been found. The analytical solution presented here is based on forces acting on a single grain in state of initiation of sediment motion. The previous procedures for calculating the initiation of sediment motion are complemented by an innovative combination of optical surface measurement technology for determining geometrical parameters and their statistical derivation as well as a novel approach for determining the turbulence effects of velocity fluctuations. This two aspects and the comparison of the solution functions presented here with the well known data and functions of different authors mainly differ the presented solution model for calculating the initiation of sediment motion from previous approaches. The defined values of required geometrical parameters are based on hydraulically laboratory tests with spheres. With this limitations the derivated solution functions permit the calculation of the effective critical transport parameters of a single grain, the calculation of averaged critical parameters for describing the state of initiation of sediment motion on the river bed, the calculation of the probability density of the effective critical velocity as well as the calculation of the risk of river bed movement. The main advantage of the presented model is the closed analytical solution from the equilibrium of forces on a single grain to the solution functions describing the initiation of sediment motion. 展开更多
关键词 土砂 底沙运动 河床运动 风险分析 光学表面测量 初始运动
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STUDY OF MORPHOLOGICAL CHANGE OF THE KUSHIYARA AND MONU RIVERS BY REMOTE SENSING 预览
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作者 M. J. B. ALAM R. ALAM, M. UDDIN T. NAHAR 《国际泥沙研究:英文版》 SCIE 2007年第2期 160-168,共9页
The Kushiyara and Monu rivers are two of the major river systems in the northeast region of Bangladesh. Analyzing satellite images of the Kushiyara and Monu rivers between 1990 and 1997, it was found that significant ... The Kushiyara and Monu rivers are two of the major river systems in the northeast region of Bangladesh. Analyzing satellite images of the Kushiyara and Monu rivers between 1990 and 1997, it was found that significant changes occurred at five distinct locations; i.e., Ahmadpur, Monumukh, Raysrr, Kaprangibari and Telibil. The amount of change was measured as 168.34 ha by using a plani-meter. Transportation of sediment was the major contributing factor of morphological change. The total average sediment concentration of Kushiyara and Monu rivers was found to be 16889.6 ppm per year during the study period by applying the Engelund and Hansen equation approach. Protection work has been suggested at the vulnerable locations. 展开更多
关键词 遥感技术 形态变化 河道保护 土砂 孟加拉国
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Indicators and impact analysis of sediment from the Changjiang Estuary and East China Sea to 预览
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作者 WANGHong FANWei YUNCaixing 《海洋学报:英文版》 SCIE CAS CSCD 2004年第2期 297-308,共12页
Based on the historical evolution of the Hangzhou Bay, by making use of the conclusions made by the previous research workers and the integration of concrete data, five distinct impact indicators of the sediment from ... Based on the historical evolution of the Hangzhou Bay, by making use of the conclusions made by the previous research workers and the integration of concrete data, five distinct impact indicators of the sediment from the Changjiang Estuary and the East China Sea to the Hangzhou Bay are summarized. Numerical calculation and analysis indicate that the scouring and deposition of seabed in the Hangzhou Bay are subject to the direct impact of the evolution of the Changjiang Estuary, and the growth and decline and the direction of the sandy bar at Nanhuizui give traces to the sediment transport between the Changjiang Estuary and the Hangzhou Bay. The transport of sediment from the Changjiang Estuary to the Hangzhou Bay occurs mainly in winter and spring seasons and the increase of the Changjiang River runoff and the decrease of sediment charge have caused scouring in the northern coast of the Hangzhou Bay and the seabed erosion along the frontal margin of the Changjiang River Delta. 展开更多
关键词 沉积学 历史演化 效果分析 土砂 杭州湾
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FLOW FIELD IN SCOURED ZONE OF CHANNEL CONTRACTIONS 预览 被引量:1
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作者 RajkumarV.RAIKAR SubhasishDEY 《国际泥沙研究:英文版》 SCIE 2004年第4期 292-311,共20页
Experiments were conducted in a laboratory flume to measure the two-dimensional turbulent flow field in the scoured zone of channel contractions under a clear-water scour condition. The Acoustic Doppler Velocimeter (A... Experiments were conducted in a laboratory flume to measure the two-dimensional turbulent flow field in the scoured zone of channel contractions under a clear-water scour condition. The Acoustic Doppler Velocimeter (ADV) was used to detect the flow field at different vertical lines along the centerline of uncontracted (main channel) and contracted zones of the channel. The distributions of time-averaged velocity components, turbulent intensity, turbulent kinetic energy, and Reynolds stresses are presented in nondimensional graphical form. The bed shear stresses are computed from the measured Reynolds stresses being in threshold condition within the zone of contraction where bed was scoured. The data presented in this paper would be useful to the investigators for the development of kinematic flow model and morphological model of scour at a channel or river contraction. 展开更多
关键词 管道收缩 腐蚀 土砂
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DESIGN OF SEDIMENT TRANSPORTING CANAL SECTIONS 预览
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作者 PrabhataK.SWAMEE NimishaSWAMEE 《国际泥沙研究:英文版》 SCIE 2004年第4期 312-318,共7页
Design equations for minimum area or maximum velocity canal-sections for transport of bulk sediment carried by water have been obtained. Such canals are economically feasible in the terrain where large slopes are avai... Design equations for minimum area or maximum velocity canal-sections for transport of bulk sediment carried by water have been obtained. Such canals are economically feasible in the terrain where large slopes are available. The design procedure is illustrated by a practical example. 展开更多
关键词 土砂 最优化 水运设计 阻力方程
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DEPTH-AVERAGED 2-D CALCULATION OF FLOW AND SEDIMENT TRANSPORT IN CURVED CHANNELS 预览 被引量:4
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作者 WeimingWU SamS.Y.WANG 《国际泥沙研究:英文版》 SCIE 2004年第4期 241-257,共17页
The helical flow significantly affects the flow, sediment transport and morphological evolution in curved channels. A semi-empirical formula is proposed to determine the cross-stream distribution of the helical flow i... The helical flow significantly affects the flow, sediment transport and morphological evolution in curved channels. A semi-empirical formula is proposed to determine the cross-stream distribution of the helical flow intensity in the developed regions of a channel bend. It is then used to evaluate the dispersion terms in the depth-averaged 2-D momentum equations and suspended-load transport equation as well as the bed-load transport angle, thus enhancing the depth-averaged 2-D model to account for the effect of helical flow. The tests in several experimental and field cases show that the enhanced depth-averaged 2-D model can much more reasonably predict the shifting of main flow from inner bank to outer bank, the erosion along outer bank and deposition along inner bank than the depth-averaged 2-D model without considering this effect. 展开更多
关键词 二阶 管道弯曲 不稳定 土砂 有限体积法
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NUMERICAL SIMULATION OF WIND-INDUCED MOTION IN SUSPENDED SEDIMENT TRANSPORT 预览
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作者 CHEN Zhi-he FANG Hong-wei LIU Bin 《水动力学研究与进展:英文版》 SCIE EI CSCD 2007年第6期 698-704,共7页
In regions with broad water surfaces such as lakes, reservoirs and coastal areas, the wind stress on the flow motion generates a significant impact. The wind stress is an unsteady force which makes numerical simulatio... In regions with broad water surfaces such as lakes, reservoirs and coastal areas, the wind stress on the flow motion generates a significant impact. The wind stress is an unsteady force which makes numerical simulation difficult. This paper presents a two-dimensional (2-D) mathematical model of the impact of wind-induced motion on suspended sediment transport at Beijing's 13-Ling Reservoir. The model uses the Diagonal Cartesian Method (DCM) with a wetting-drying dynamic boundary to trace variations in the water level. The calculation results have been tested against in situ measurements. The measurements confirm the model's accuracy and agreement with the actual situation at the reservoir. The calculations also indicate that wind stress holds the key to suspended sediment transport at Beijing's 13-Ling Reservoir, especially when westerly winds prevail. 展开更多
关键词 数值模拟 体力学 风压 笛卡尔模型 悬浮土砂
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VERIFICATION OF MATHEMATICL MODEL FOR SEDIMENT TRANSPORT BY UNSTEADY FLOW IN THE LOWER YELLOW RIVER 预览
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作者 JianjunZHOU BingnanLIN 《国际泥沙研究:英文版》 SCIE 2004年第4期 278-291,共14页
Field data from the Lower Yellow River (LYR) covering a period of ten consecutive years are used to test a mathematical model for one dimensional sediment transport by unsteady flow developed previously by the writers... Field data from the Lower Yellow River (LYR) covering a period of ten consecutive years are used to test a mathematical model for one dimensional sediment transport by unsteady flow developed previously by the writers. Data of the first year of the said period, i.e., 1976, are used to calibrate the model and those of the remaining years to verify it. Items investigated include discharge, water stage, rate of transport of suspended sediment and riverbed erosion/deposition. Comparisons between computed and observed data indicate that the proposed model may well simulate sediment transport in the LYR under conditions of unsteady flow with sufficient accuracy. 展开更多
关键词 悬浮土砂 不稳定 数学模型 LYR
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