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91.
ZHOU Jianjun LIN Binganand WANG Lianxiang Dr. of Eng. Research engineer the Institute of Water Conservancy Hydroelectric Power Research 《国际泥沙研究》1991,(1)
A new mathematical model for 2-D flow is formulated with accurate satisfac tion of boundary conditions in conjunction with square or any grids,so that it may also yield accurate results when the domain of computation is in the shape of a strip as occurring in rivers. The basic equations are split into three sets of compo- nent equations of which two sets may be transformed to the same form. This model is a part or a model devised for 2-D flows with sediment. 相似文献
92.
Zhaoyin WANGProf Dr. International Research Training Center on Erosion Sedimentation. P.O.Box Beijing China Jinchi HUANG Dr. Senior Engineer China Institute of Water Resources Hydro-Power Research P.O.Box Beijing . Chi 《国际泥沙研究》1997,(3)
I.INTRODUCTIONhiverchannelsaresubjecttocontinuouschangeingeometryduetoillteraCtionbetWeentheflowanderodibleboundaries.Ofconcerntothedesignersofoilpipelinesacrossariver,bridgesandhydraulicworksistheproblemofscourwhichcanunderminetheStructures.Scouratsiteofbridgesandhydraulicworksoccursduetoconstrictedflowandexistenceofbridgepiers.SuchatabOfscouroccursonlyinashortsection,usuallyillthesameorderofthelengthofthehydraulicworksorbridges.Therefore,thispatternofscouriscalledlocalscour.Man}rresea… 相似文献
93.
Helmut M.HABERSACK Research Assistant Institute for Water Management Hydrology Hydraulic Engineering Universitaet fuer Bodenkultur Muthgasse Vienna Austria 《国际泥沙研究》1997,(3)
1.INTRODUCTIONOVerthelastdecadesmuchprogresshasbeenmadeconcerningsedimenttransPOrtmodellingandmonitoring.Thedifferelltiationincatchmeflt-tvide,sectionalandlocalaspectsreflectsthefactthatmanysedimenttransportandpredictionmodelsaredealingwithspecialpartsofriverSystems,mainlydifferinginscale.Overthepastyears,scaleissuesinhydrologyhaverapidlyincreasedinimportance(BLoSCHL,1996).Onalargescaletheapplicationoffractals,self-similarityanalysistolandscapeorganizationandoptimalchannelnetlvorks(O… 相似文献
94.
1 BACKGROUND The Kankakee River, which straddles the States of Indiana and Illinois in the Midwest, is shown in Fig. 1. This figure also shows the dividing line between these two states and the streamgaging and few sediment gaging stations in the basin. The main stem of the river in Indiana was channelized, thus bypassing numerous oxbows, meanders, side channels, etc., that existed before the 1890s. Before channelization in Indiana, the river essentially flowed through a wetland/mar… 相似文献
95.
1 INTRODUCTION The coherent structure of turbulence is the most important discovery of turbulence studies in the last several decades. The coherent structure is a joint spatial state (Liang, 1999). In this space, there exist all kinds of motions that are organized and related. Namely, strip structures, large vortical structures, and other organizing flows are present. In 1932, researchers found that turbulence wasn抰 a fully random phenomenon and came to realize that the repeated emergen… 相似文献
96.
97.
次降雨条件下坡面侵蚀形态的演变过程和细沟的发生发展过程是土壤侵蚀规律研究中的重点和难点。利用REE示踪法,采取沿坡面垂直分层布设的新的试验方法,通过室内模拟降雨试验,对坡面侵蚀演变过程进行了探索性研究。结果表明:降雨初期坡面侵蚀以面蚀为主,细沟出现后,坡面侵蚀加剧;随着降雨时间的延续,累积面蚀量和细沟侵蚀量逐渐增加,但后者的增加速率大于前者,面蚀占总侵蚀量的比率随降雨时间呈曲线形式逐渐递减,细沟侵蚀则逐渐增加;试验结束时细沟侵蚀量为面蚀量的2~4倍。本研究为定量区分和研究坡面侵蚀过程中面蚀和细沟侵蚀量,面蚀向细沟侵蚀的转变以及细沟侵蚀发生、发育提供了新的思路和解决途径。 相似文献
98.
A vertical 2-D numerical model is presented for simulating the interaction between water waves and a soft mud bed. Taking into aceotmt nonlinear theology, a semi-empirical theological model is applied to this water-mud model, reflecting the combined visco-elasto-plastic properties of soft mud under such oscillatory external forces as water waves. In order to increase the resolution of the flow in the neighborhood of both sides of the inter-surface, a logarithmic grid in the vertical direction is employed for numerical treatment. Model verifications are given through comparisons between the calculated and the measured mud mass transport velocities as well as wave height changes. 相似文献
99.
Weng Keqin Chen Luhua
Engineer Planning Design Institute for Water Transportation Ministry of Communications Beijing 《中国海洋工程》1991,(1)
This paper, based on wave data measured with Type 956 Directional WAVE-TRACK Buoy System at new Dalian Port for a whole year, analyses the properties of the wave frequency spectra, and derives the formula for the frequency spectrum of wind-waves. 相似文献
100.
高喷灌浆在长善垸浏阳河防洪大堤第四系松散地基的防渗、加固中效果显著,与其它防渗措施比较,其施工速度快,成本低,在深度覆盖层堤基防渗中显示出无可比拟的优越性。 相似文献