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Acta Oceanologica Sinica 2000年第1期19卷 145-154页

作者： Dong Wenjun Bai Yuchuan Li Shisen (1. department of Mathematics, Tianjin University, Tianjin 3.0072, China 2. department of hydraulics, Tianjin University, Tianjin 3.0072, China) department of Mathematics Tianjin University Tianjin 300072 China department of hydraulics Tianjin University Tianjin 300072 China

A calculation scheme, which combines a horizontal upwind finite element method with vertical implicit differences, is used to establish a three-dimensional mathematical model of tidal motion and sediment transport in tidal current. Compared with those of the relative theoretical formula, the results are satisfactory. The model mentioned above has been applied to the water area of the Lianzhou Bay, Guangxi Province. On the basis of the analysis and comparison with the field data, it shows clearly that the model calculation results are reasonable.

关键词： Tidal current sediment transport in tidal current upwind finite element three- dimensional numerical simulation

A third-order asymptotic solution of nonlinear standing water waves in Lagrangian coordinates

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Chinese Physics B 2009年第3期18卷 861-871页

作者：陈益处许弘莒 department of Marine Environment and Engineering National Sun Yat-Sen University Tainan hydraulics Laboratory National Cheng Kung University

Asymptotic solutions up to third-order which describe irrotational finite amplitude standing waves are derived in Lagrangian coordinates. The analytical Lagrangian solution that is uniformly valid for large times satisfies the irrotational condition and the pressure p = 0 at the free surface, which is in contrast with the Eulerian solution existing under a residual pressure at the free surface due to Taylor＇s series expansion. In the third-order Lagrangian approximation, the explicit parametric equation and the Lagrangian wave frequency of water particles could be obtained. In particular, the Lagrangian mean level of a particle motion that is a function of vertical label is found as a part of the solution which is different from that in an Eulerian description. The dynamic properties of nonlinear standing waves in water of a finite depth, including particle trajectory, surface profile and wave pressure are investigated. It is also shown that the Lagrangian solution is superior to an Eulerian solution of the same order for describing the wave shape and the kinematics above the mean water level.

关键词： Lagrangian nonlinear standing waves particle trajectory Lagrangian wave frequency

Dynamic Responses of Block Type Quay Walls Under Cyclic Loading

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China Ocean Engineering 2021年第2期35卷 281-290页

作者： Hulya Karakus CIHAN Kubilay CIHAN Yuksel Project 06610 CankayaAnkaraTurkey Civil Engineering department Hydraulics DivisionKırıkkale UniversityKırıkkaleTurkey

The purpose of this research is to study the dynamic responses of gravity quay walls with block type consisting of“three blocks”*** this purpose,1g shaking table tests were conducted under different cyclic loadings for two different saturated granular backfill materials(Soil 1 and Soil 2).In this study,D_(n50) of Soil 1 and Soil 2 are selected as 2.2 cm and 1.0 cm,*** the experiments,accelerations,soil pressures and displacements were measured for each *** results pointed out that Soil 2 caused more damage on *** measurements for displacement and tilting of each block were discussed in view of“acceptable level of damage in performance-based design”given in PIANC(2001).The result of the study showed that the definitions of damaged levels given in PIANC(2001)were reliable for using in performance-based methods for seismic design of block type quay walls.

关键词： block type quay walls 1g shaking table tests damage level dynamic response

On the way to airborne gravelometry based on 3. spatial data derived from images

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International Journal of Sediment Research 2018年第1期33卷 84-92页

作者： M.Detert L.Kadinski V.Weitbrecht Laboratory of hydraulics Hydrology and Glaciology VAWETH Zurich

This paper presents basic tests to develop an airborne photogrammetric methodology that derives grain size characteristics of gravel bed rivers. The data acquisition was done using a light weight action cam and a hand-held digital single lens reflex camera. Image processing comprised the structure from motion technique and multiview-stereo algorithms to obtain digital elevation models of non-cohesive gravel beds. Laboratory results indicate that the method accuracy is about four to six times lower than laserscan data when based on action cam data. The accuracy of digital elevation models computed via photos taken by the reflex camera is almost of the same range as the laser data. Field experiments were done to test the performance of image based gravelometry against manual surface sampling. For this application the action cam was mounted to a low-cost quadrocopter, while the reflex camera was operated by *** indicate that this combination has a high potential to generate data from which characteristic grain size parameters can be estimated.

关键词： Airborne photogrammetry Grain size distribution Gravel bed Field work Gravelometry Image analysis Laboratory experiments Structure from motion Surface sampling

Study of water intakes for oncomelania control based on information of oncomelania behavior and CFD results

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Science China(Technological Sciences) 2001年第5期44卷 522-530页

作者：李大美王祥三赖永根 department of River Engineering Wuhan University Wuhan 430072 China Iowa Institute of hydraulics the University of Iowa Iowa City IA USA

Schistosomiasis is a parasitic disease. They propagate in the Yangtze River valley of Chi-na. The spread of the disease is solely through a middle-agent named oncomelania, so the spread ofschistosomiasis by oncomelania can be controlled by properly designing water intakes which preventoncomelania from entering the farming land or residential areas. In this paper, a successful design pro-cess is reported and a new oncomelania-free intake device is demonstrated in the laboratory. The de-sign of the new intake is based on a sound research program in which an extensive experimental stud-ies have been carried out to gain knowledge of oncomelania eco-hydraulic behaviors and a detailed flowfield information is obtained through CFD simulation.

关键词： oncomelania control ecologic hydraulic CFD oncomelania-free intake

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science China Earth Sciences 2024年第5期67卷 1529-1544页

作者： Chuan YUAN Xiaoping YUE Yafeng ZHANG Yu ZHANG Yanting HU Qiang TANG Li GUO Shuai WANG Xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community *** advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely *** address this gap,we conducted a systematic review of 1020 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3.^(-)and SO_(4)^(2-))from the Web of Science and Chinese Knowledge Infrastructure *** aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and *** results of this study indicate that stemflow exhibits,on average,2.1times greater ion concentration(6.13.mg L^(-1))compared to *** particular,among the investigated ions,SO_(4)^(2-)(12.45and 6.3. mg L^(-1))for stemflow and throughfall,respectively,and Cl^(-)(9.21 and 4.81 mg L^(-1))exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(13.7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment *** climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid *** the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing *** addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural *** findings emphasize the need for increased attentions to artificial ecosystems,such as urban

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

Influence of surface roughness of dune bedforms on flow and turbulence characteristics

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International Journal of Sediment Research 2020年第6期35卷 666-678页

作者： Veysel Sadan Ozgur Kirca Seyed Mahdi Saghebian Kiyoumars Roushangar Oral Yagci Istanbul Technical University Department of Civil Engineering department of Civil Engineering Ahar Branch Islamic Azad University Division of hydraulics Department of Civil EngineeringUniversity of Tabriz

The current paper investigates the flow and turbulence characteristics over dune bedforms by means of laboratory experiments,where spatially dense and temporally high frequency velocity measurements were *** similar studies are available in the literature,the focus and novelty of the current study is to assess the influence of surface roughness of the dune bedforms on the nearbed *** direct comparison,two different surface roughness heights over idealized,fixed-shaped,high-angled dune bedforms were tested;one with a hydraulically-smooth surface,and the other with a fully-rough *** variation of time-averaged flow as well as turbulence statistics were examined,which was complemented by streamline plots and spectral *** results are interpreted from sediment entrainment and sediment transport points of *** results show that increased dune surface roughness reduces the nearbed flow velocity,but increases the flow velocities at upper *** upward directed flow near the dune crests becomes stronger in the case of smooth surface,while the reattachment point moves further downstream compared to the rough wall *** is concluded that the roughness of the dune surface affects the nearbed flow and turbulence characteristics qualitatively and quantitatively,which is shown to have direct consequences on sediment entrainment characteristics.

关键词： Bedforms Dunes Friction drag Turbulence Grain roughness Form drag

Breathing architecture： Conceptual architectural design based on the investigation into the natural ventilation of buildings

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Frontiers of Architectural Research 2015年第2期4卷 127-145页

作者： Anastasia D. Stavridou Division of hydraulics and Environmental Engineering Department of Civil Engineering Aristotle University of Thessaloniki 54124 Thessaloniki Greece

This study explores architectural design by examining air, fluid mechanics, and the natural ventilation of buildings. In this context, this research introduces a new way of dealing with the process of architectural synthesis. The proposed way can be used either to create new architectural projects or to rethink existing ones. This study is supported by previous investigation into the natural ventilation of buildings via computational and laboratory simulation （Stavddou, 2011; Stavridou and Prinos, 2013.. The investigation into the natural ventilation of buildings provides information and data that affect architectural design through various parameters. The parameters of architectural synthesis that are influenced and discussed in this paper are the following：（i） inspiration and analogical transfer, （ii） initial conception of the main idea using computationat fluid dynamics （digital design）, （iii） development of the main idea through an investigatory process toward building form optimization, and （iv） form configuration, shape investigation, and other morphogenetic prospects. This study illustrates the effect of natural ventitation research on architectural design and thus produces a new approach to the architectural design process. This approach leads to an innovative kind of architecture called ＂breathing architecture.＂

关键词： Natural ventilation of buitdings Computational fluiddynamics Architectural desisn Architectural synth-esis Air Concept

Tidal analysis in the venturi-shaped area between Zhenhai and Shenjiamen in the East China Sea

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Chinese Journal of Oceanology and Limnology 2009年第1期27卷 103-111页

作者：吕华庆胡建炯 Marine Science School of Zhejiang Ocean University Zhejiang Institute of hydraulics & Estuary

In order to better understand the general tidal features in the venturi-shaped area between Zhenhai and Shenjiamen in the northern coastal region of Zhejiang Province in the East China Sea, the tidal data were obtained from both the three permanent tide stations of Zhenhai, Dinghai and Shenjiamen, and four temporary tide stations of Mamu, Chuanshan, Guoju and Liuheng, along with the current speed being observed at Luotou Waterway. Results from harmonic analysis show that: (1) The area was dominated by shallow water tides with irregular semi-diurnal features, and the smallest tidal range occurred in the area near a crossing line between Zhenhai and Dinghai stations, indicating that a tidal node existed in the southern Hangzhou Bay; (2) Formulae, HS2/HM2 >0.4 and gM2-(gK1+gO1)=270° (where H and g are harmonic constants), could be used as judging criteria for high and low tidal level diurnal inequalities; (3. The duration difference between ebb and flood tides could be roughly assessed by the ratio of HM4 vs. HM2; and the larger the ratio is, the bigger the duration difference is. At the same time, the duration period could be assessed by 2gM2-gM4, the epoch difference between M2 and M4 tidal constituents. If 2gM2-gM4 3.0°, the result is reversed; (4) Taking Dinghai station as a center point, the highest tidal levels and the average high tidal levels, as well as the average tidal ranges at all stations became higher and larger both southeastwards and northwestwards, while the lowest tidal levels and the average low tidal levels appeared to be lower both southeastwards and northwestwards; and (5) The tidal patterns were not all in line with the tidal current patterns. As a conclusion, the smallest tidal range occurred in the narrow part of the venturi-shaped area. Along the both sides of the area, the highest tidal level and tidal range became higher and larger, while the lowest tidal lev

关键词： East China Sea harmonic analysis Luotou Waterway tidal features venturi-shaped area Zhejiang coastal water

Meshless Method with Domain Decomposition for Submerged Porous Breakwaters in Waves

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Journal of Ocean University of China 2021年第6期20卷 1325-1340页

作者： CHIOUKH Nadji YÜKSEL Yalçın department of hydraulics University of Sidi Bel-AbbesSidi Bel-Abbes 22000Algeria Laboratory of Civil Engineering and Environment University of Sidi Bel-AbbesSidi Bel-Abbes 22000Algeria Laboratory of hydraulics and Coastal Engineering Yildiz Technical UniversityEsenler-Istanbul 34220Turkey

Based on the improved version of the meshless singular boundary method(ISBM)in multi domain(MD),a numerical method is proposed in this paper to study the interaction of submerged permeable breakwaters and regular waves at normal *** account for fluid flow inside the porous breakwaters,the conventional model of Sollitt and Cross for porous media is *** single and dual trapezoidal breakwaters are *** physical problem is formulated in the context of the linear potential wave *** domain decomposition method(DDM)is employed,in which the full computational domain is decomposed into separate domains,that is,the fluid domain and the domains of the ***,appropriate mixed type boundary and continuity conditions are applied for each subdomain and at the interfaces between *** solution is approximated in each subdomain by the *** discretized algebraic equations are combined,resulting in an overdetermined full system that is solved using a least-square solution *** numerical results are presented in terms of the hydrodynamic quantities of reflection,transmission,and wave-energy *** relevance of the results of the present numerical procedure is first validated against data of previous studies,and then selected computations are discussed for various structural *** proposed method is demonstrated to be highly accurate and computationally efficient.

关键词： meshless method domain decomposition regular waves breakwaters porosity reflection transmission dissipation coastal environment