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Modeling of erosion and deposition on rough test limiter exposed to the edge plasma of TEXTOR

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Modeling of erosion and deposition on rough test limiter exp...

Exploration of the Mechanisms for the Low Sensitivity of deposition Flux to Upstream Sediment Reduction in the North Passage, Yangtze Estuary

第十五届全国等离子体科学技术会议

作者： Zhanfu Yao~,Jizhong Sun and Dezhen Wang Key Laboratory of Materials Modification by Laser,Ion and Electron Beams(Ministry of Education),School of Physics and Optoelectronic Technology,Dalian University of Technology, Dalian 116024,China

Experiments carried out at TEXTOR showed that the carbon deposition efficiency from externally injected methane on rough(lμm) test limiters is much larger(up to a factor of 5) than on more smooth(0.1μm) ones.Also the deposition pattern on the rough surfaces is broader.To understand the involved processes a special Surface Roughness Code(SRC),which takes into account the erosion,deposition and surface

关键词： erosion and deposition SOL

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中国海洋工程:英文版 2023年第4期37卷 533-546页

作者： WANG Xiao-guang ZHANG Wei TONG Chao-feng LEI Zhi-yi QIN Jie JI Xiao-mei HUANG Rui The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Deltas are densely populated industrialized regions,and home to important ports and navigation channels.Due to human interferences,the Yangtze Estuary has experienced a significant reduction in sediment load caused by the Three Gorges Dam(TGD),as well as adjustment to local morphodynamics by the Deep-water Navigation Channel(DNC).While the dramatic reduction in sediment triggers the increased channel erosion,the deposition flux of the DNC located at the estuary mouth has little change.To explore the physical mechanism of this phenomenon,a two-dimensional model is used to establish the relationship between sediment load and the sediment budget of channels based on the bathymetry in 2016.Model results show that the tidal reach and the inner estuary have a negative sediment budget.And the seasonal characteristics of water and sediment fluxes become less obvious downstream.Sensitivity analysis shows that the influence of upstream sediment load on deposition flux decreases along the channel,with a transition from deposition to erosion occurring in the tidal reach.For the last-level bifurcation,the annual siltation of sediment in the North Passage(NP)decreases by 4.5%with low sensitivity.This is attributed to the reduction of sediment load partially mitigated by riverbed erosion and cascade bifurcations.In addition,the lateral sediment supply,which accounts for 68%of the sediment input in the NP,is stable.Overall,this study strengthens the understanding of the relationship between sediment load and artificially deepened systems,thus allowing for better management of estuarine sediment and navigation channel.

关键词： delta navigation channel sediment load erosion and deposition sediment budget Yangtze Estuary

Quantitative analysis on the dynamic characteristics of megadunes around the Crescent Moon Spring, China

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Journal of Arid Land 2014年第3期6卷 255-263页

作者： YingJun PANG JianJun QU KeCun ZHANG ZhiShan AN QingHe NIU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Gansu Center for Sand Hazard Reduction Engineering and Technology

The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics and changes of megadunes around the Crescent Moon Spring by interpreting aerial photographs taken in 1985 and 2004 and analysing the dune crestlines and the wind data collected from 2011 to 2012. Results revealed that pyramid dunes were formed by a complex wind regime. The Crescent Moon Spring was not buried by shifting sands because of the stable wind regime and relative stability of pyramid dunes. The crestlines of the dunes around the spring moved northward between 1985 and 2004. The south-facing slip faces were also exposed to wind ero- sion, whereas the other faces were under deposition, thus indicating that the southerly wind was relatively en- hanced. Limiting the scale of tall windbreaks and architectures in the Dunhuang oasis at the north of the spring was necessary to maintain the dynamic equilibrium of the wind regime and sand transport.

关键词： Dunhuang city Crescent Moon Spring pyramid dunes dynamic characteristics erosion and deposition

Evolution of river course and morphometric features of the River Ganga:A case study of up and downstream of Farakka Barrage

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International Soil and Water Conservation Research 2021年第4期9卷 578-590页

作者： Md Nawaj Sarif Lubna Siddiqui Md Safikul Islam Neha Parveen Monojit Saha Department of Geography Jamia Millia IslamiaNew DelhiIndia Centre for Earth Observation science University of ManitobaCanada

River channel shifting in the deltaic regime is an unabated occurrence.Channel shifting has become one of the concerns as it influences land use/land cover along the riverbank in various ways.For the management of the river,it is indispensable to study the pattern of river course change both in qualitative and quantitative methods.This study is an attempt to understand the pattern of shifting and to quantify erosion and deposition of the river Ganga at upstream and downstream of Farakka Barrage during 1794-2017.The study has been carried out by using various historical maps,aerial photographs,satellite imagery,and remote sensing and GIS technique to understand the dynamic of the river.Over 223 years period shifting of the river accentuates the remarkable oscillation of the river.Perimeter of the river is determined to understand the area covered by the river course in the study area.To evaluate the meandering of the river sinuosity of the river has been computed in this study.The amount of erosion and deposition was calculated in this study by using ArcGIS 10.6.The study found a higher amount of erosion at the east bank where Manikchak,Kaliachak II and Kaliachak III blocks are situated between 1965 and 2017.At the west bank of the river,especially the Rajmahal block,the occurrence of deposition was remarkable during the same period.

关键词： River shifting Sinuosity Ganga erosion and deposition Landsat

RANGE SURVEY OF deposition IN THE LOWER YELLOW RIVER

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International Journal of Sediment Research 2002年第2期17卷 91-101页

作者： LONG Yuqian1, LIANG Guoting1, ZHANG Yuanfeng1, SHEN Guanqing1, ZHANG Liuzhu1 and CHENG Longyuan1 Yellow River Conservancy Commission Zhengzhou 450003 Henan P.R.China

A range survey database is established and used to study the deposition or erosion processes in the Lower Yellow River (LYR). The huge amount of data obtained through range surveys over nearly 50 years is managed by software (RGTOOLS) developed for this study. RGTOOLS is also used to evaluate the amount and distribution of deposition or erosion in LYR. Volumetric method is used for computation of the amount of deposition. Spatial and temporal variations of the deposition are studied and illustrated with drawings. It is found that a total of 6.44 billion m3 of sediment were deposited in the lower Yellow River over approximately 50 years. The pattern of deposition varies in response to the variation of oncoming flow, which is influenced by natural climatic variations and also by reservoir operation.

关键词： Lower Yellow River Range survey database erosion and deposition Volumetric method

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长江口冲淤交替及变化趋势

Journal of Geographical Sciences 2020年第1期30卷 145-163页

作者：朱博渊李义天岳遥杨云平梁恩航张春财 BORTHWICK Alistair G.L. School of Hydraulic Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China School of Water Resources and Hydropower Engineering State Key Laboratory of Water Resources and Hydropower Engineering ScienceWuhan UniversityWuhan 430072China Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of TransportTianjin 300456China The Key Laboratory of Water and Sediment Sciences Ministry of EducationCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China School of Engineering The University of EdinburghThe King’s BuildingsEdinburgh EH93JLUK

The morphological changing trend of the Yangtze Estuary,the largest estuary of Asia,has become a focus of research in recent years.Based on a long series of topographic data from 1950 to 2015,this paper studied the erosion-deposition pattern of the entire Yangtze Estuary.An alternation between erosion and deposition was found during the past 65 years,which was in correspondence to the alternation between flood and dry periods identified by multi-year average duration days of high-level water flow(defined as discharge≥60,000 m 3/s,namely,D≥60,000)from the Yangtze River Basin.A quantitative relationship was further developed between the erosional/depositional rate of the Yangtze Estuary and the interpreting variables of yearly water discharge,D≥60,000 and yearly river sediment load,with contributing rates of 1%,59%and 40%,respectively.Mechanism behind the alternate erosion and deposition pattern was analyzed by examining residual water surface slope and the corresponding capacity of sediment transport in flood and dry periods.In flood periods,a larger discharge results in steeper slope of residual water level which permits a greater capacity of sediment transport.Therefore,more bed materials can be washed to the sea,leading to erosion of the estuary.In contrast,flatter slope of residual water level occurs in dry periods,and deposition dominates the estuarine area due to the decreased capacity of sediment transport and the increased backwater effect of flood-tide.Coastal dynamics and estuarine engineering projects alter the local morphological changes,but slightly affect the total erosional/depositional rate of the whole estuarine region.Heavy sedimentation within the Yangtze Estuary after the impoundment of the Three Gorges Dam can be attributed to the reduced occurrence frequency of flood years due to water regulation by the dam,and largely(at least 36%-52%)sourced from the sea.deposition is still possible to occur in the Yangtze Estuary in the future,because the multi-year average D≥60,000 is unlikely to exceed t

关键词： Yangtze Estuary erosion and deposition alternation total sediment load evolutional trend

PREDICTION OF IMPACT OF THE THREE GORGES PROJECT ON ESTUARY BEACH OF THE YANGTZE RIVER

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International Journal of Sediment Research 1998年第1期 47-54页

作者： Weibing FENG 1\ Yigang WANG 2 and Xiucheng ZHONG 3

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ＰＲＥＤＩＣＴＩＯＮＯＦＩＭＰＡＣＴＯＦＴＨＥＴＨＲＥＥＧＯＲＧＥＳＰＲＯＪＥＣＴＯＮＥＳＴＵＡＲＹＢＥＡＣＨＯＦＴＨＥＹＡＮＧＴＺＥＲＩＶＥＲＷｅｉｂｉｎｇＦＥＮＧ１ＹｉｇａｎｇＷＡＮＧ２ａｎｄＸｉｕｃｈｅｎｇＺＨＯＮＧ３ＡＢＳＴＲＡＣＴＡｌｔｈｏ...

关键词： Estuary beach Annual sediment load erosion and deposition The Three Gorges Project Estuary evolution