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Wave Reflection Caused by Wave Overtopping and Sloping Top of Spructure

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China Ocean Engineering 2002年第2期17卷 211-218页

作者：李炎保谷汉斌张绍松 Department of Port and Coastal Engineering

In this paper, the theoretical analysis and experimental studies are employed to investigate the reflection characteris-tics of partial standing waves caused by wave overtopping and Sloping top of structures. Based on the principle of conser-vation of wave energy flux, the third-order Stokes wave theory is used to formulate the reflection coefficient at wave over-topping; the calculation results are regressed into an applied expression. A series of experiments of wave reflection for avertical-wall structure with chanffered and overhanging upper sections are carried out to investigate the influence of topslope on wave reflection. The regularity of variation of wave reflection in this ease is analysed based on the experimentalresults.

关键词： reflection coefficient partial standing waves overtopping Sloping top of structure

A New Rainwater Harvesting and Recycling System for Transforming Sloping Land into Terraced Farmland

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Journal of Mountain Science 2014年第1期11卷 205-214页

作者： SHI Yuan-zhi WANG Yue-hong CUI Yuan-lai WANG Shi-wu ZHANG Yu-shuai State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Water Resources and Hydropower Bureau of Fuyang City Zhejiang Institute of Hydraulics and Estuary

Transforming Sloping land into terraced land is an effective approach to cope with the problems including farmland shortage and severe soil erosion.This paper introduces a new system based on rainwater harvesting and recycling technology,which may effectively improve farmland productivity rainwater use efficiency and reduce water and fertilizer inputs.The new system consists of three subsystems：1） A plough layer with the dual function of crop cultivation and rainwater harvesting; 2） A tank below the plough layer for storing water; 3） An irrigation-drainage subsystem.The plough layer and the storage tank,both treated for reducing seepage,are connected through the irrigation and drainage system.Results showed that,compared with the traditional paddy fields,rice evapotranspiration（ and crop coefficient） in the test field remained at a similar level,while the irrigation amount was reduced by 44.3% under the condition of basin irrigation,and the drainage amount decreased by 86.6%,and the non-point source pollution was reduced to 67.7%~87.9%,and the rainwater utilization efficiency increased by 30% and reached 95.4%,and crop yield of middle-season rice reached 9,975 kg/hm2,which was only 0.4% lower than that in the traditional paddy field in the terms of dry matter.The new technology sheds light on new possibilities for transformation of hilly Sloping land.

关键词： Hills Sloping land Terraced farmland Rainwater harvesting Recycling

Profile Distribution of Soil Properties on Sloping Cropland in Yingwugou Small Watershed of the Dan River Basin

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Asian Agricultural Research 2013年第10期5卷 111-116页

作者： Guoce XU Zhanbin LI Peng LI Tiegang ZHANG Haidong GAO Key Lab of Northwest Water Resources and Environment Ecology of Ministry of Education Xi'an University of Technology State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources

Based on 3 m×3 m grid in Sloping cornfield with soil auger in Yingwugou Small Watershed of the Dan River Basin,a total of 39sampling points were collected,and soil water content and nutrient content were measured in different soil depths.Meanwhile,the soil properties of different depth have been analyzed by traditional statistical and geo-statistics approaches.The results showed:the mean value of total nitrogen and soil organic carbon reduced as soil depth increased in general.But soil water content increased as the soil depth increased.The change of total phosphorus with soil depth was not obvious.The total nitrogen,soil water content,soil organic carbon and total phosphorus presented a moderate intensity variation and strong spatial dependence.In the four sampling depths,semi-variance model can simulate spatial structure of total nitrogen,soil water content and total phosphorus in 0 to 10 cm and 10 to 20 cm well.But the spatial structure of soil organic carbon was not good,which could not be simulated with semi-variance model.The analysis with Kriging interpolation showed that,the total nitrogen,soil water content and total phosphorus presented layered distribution in 0 to 10 cm and 10 to 20 cm;when the spatial distribution changed to 10 to 20cm from 0 to 10 cm,the average total nitrogen content reduced to from 0.598 g/kg 0.310 g/kg,while the average soil water content and total phosphorus increased from 12.988%to 15.439%and from 0.229 g/kg to 0.366 g/kg,respectively.

关键词： Sloping cropland TN TP Soil organic carbon Profile

Merging Effluent Discharge Plumes from Multiport Diffusers on a Sloping Beach

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Applied Mathematics 2012年第1期3卷 24-29页

作者： Anton Purnama Department of Mathematics and Statistics College of Science Sultan Qaboos University

Multiport diffusers are the effective engineering devices installed at the marine outfall systems for the steady discharge of effluent streams from the modern coastal plants, such as municipal sewage treatment, power generation and seawater desalination. A far field mathematical model using a two-dimensional advection-diffusion equation is presented for continuous discharges of effluent streams from multiple outfalls on a uniformly Sloping beach with a current parallel to the shoreline. The analytical solutions are illustrated graphically to replicate and capture the merging process of effluent plumes in shallow coastal waters, and then asymptotic approximation will be made to the maximum shoreline’s concentration to formulate effluent discharge plume dilution from a multiport diffuser.

关键词： Effluent Discharge Mathematical Model Multiple Outfalls Multiport Diffuser Sloping Beach

High-Order Models of Nonlinear and Dispersive Wave in Water of Varying Depth with Arbitrary Sloping Bottom

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China Ocean Engineering 1997年第3期12卷 243-260页

作者： Hong Guangwen Professor, Coastal and Ocean Engineering Research Institute, Hohai University, Nanjing 210024, P. R. China. Coast. and Ocean Eng. Res. Institute Hohai University Nanjing 210024 China

High-order models with a dissipative term for nonlinear and dispersive wave in water of va-rying depth with an arbitrary Sloping bottom are presented in this article.First,the formal derivations toany high order of μ(=h/λ,depth to deep-water wave length ratio)and ε(=α/h,wave amplitude todepth ratio)for velocity potential,particle velocity vector,pressure and the Boussinesq-type equations forsurface elevation η and horizontal velocity vector U at any given level in water are given.Then,the exactexplicit expressions to the fourth order of μ are derived.Finally,the linear solutions of η,U,C(phase ce-lerity)and C_g(group velocity)for a constant water depth are obtained.Compared with the Airy theory,excellent results can be found even for a water depth as large as the wave legnth.The present high-ordermodels are applicable to nonlinear regular and irregular waves in water of any varying depth(from shal-low to deep)and bottom slope(from mild to steep).

关键词： nonlinear wave dispersive wave high order models boussinesq-type equations varying depth arbitrary Sloping Bottom

Experimental Study on the Armor Grate Plate of Sloping Breakwater Under the Action of Irregular Waves

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China Ocean Engineering 1997年第1期12卷 89-98页

作者： Wu, GQ Meng, XD Zhang, HY Zhang, JZ OCEAN UNIV QINGDAO QINGDAO 266003PEOPLES R CHINA

The irregular wave experiment on the stability of the Grate Plate was carried out in the lightof the wind wave spectrum recently advanced by Prof.Wen Shengchang.The stability formulas of GP un-der the action of irregular waves were procured.Comparisons between the formulas obtained and those ofGP under regular waves advanced by the first author in 1993 showed a coincident result.

关键词： Sloping breakwater grate plate irregular waves wave spectrum

EFFECTS OF A Sloping THERMOCLINE AND RAYLEIGH FRICTION ON EQUATORIALLY TRAPPED KELVIN WAVES

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Chinese Journal of Oceanology and Limnology 1999年第3期17卷 265-270页

作者：陈学恩吴德星青岛海洋大学物理海洋所山东青岛

Based on the observed equatorial ocean dynamic characteristics, the effects of a Sloping thermocline and Rayleigh friction on the equatorially trapped free Kelvin waves were theoretically studied with a linear one and one half layer reduced gravity model, the multiple scale method and a small parameter expansion technique. Assuming that main thermocline depth (MTD) variations are slow, i.e. the changes of MTD over one wavelength are smaller than that of the wave amplitude and that wave reflections are negligible, the authors showed by their analytical results that the wavelengths and amplitudes of Kelvin waves are significantly modified by the MTD variations and Rayleigh friction. The results also showed that for an eastward shallowing thermocline, the zonal velocity of the Kelvin waves varies with thermocline depth to the power -7/8. The eastward shallowing of the thermocline depth strengthens Kelvin wave entrapment at the equator. Rayleigh friction reduces the Kelvin wave’s eastward velocity while the thermocline acts in the opposite way. The friction causes dispersion of the Kelvin wave, whose dissipation factor does not depend on its wavelength. The friction increases the lateral decay length and causes phase lines of Kelvin waves to slant westward in parabolic arcs.

关键词： equatorially trapped Kelvin waves Sloping thermocline Rayleigh friction

EFFECTS OF Sloping BOTTOM ON THE DEEPCROSS-EQUATORIAL BOUNDARY CURRENT

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Chinese Journal of Oceanology and Limnology 1997年第1期15卷 65-69页

作者：吴德星吕红民郭群卢镇 Institute of Physical Oceanography Qingdao Ocean University Qingdao

This paper reports study focusing on the effects of Sloping bottom on the deep cross-equatorial boundary current, and discusses model and laboratory experiment results showing that the southward that the southward intrusion distance and flow speed of the western boundary current depend on the bottom slope variation rate,the difference between and and are the current thickness at eastward edge and westward edge, respectively), and the net mass transport.

关键词： deep cross-equatorial boundary current effects of Sloping bottom laboratory turntable experiment

PROPAGATION AND BREAKING OF WAVES ON Sloping BEACH

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Journal of Hydrodynamics 1993年第1期5卷 1-9页

作者： Chen, Miaofu Zhao, Yaonan Tianjin Univ Tianjin China

In this paper the propagation and breaking of the solitary wave,the sinusoidalwave and the second Stokes wave on a slope of 1/30 are discussed based upon the TUMMACmethod,and the velocity fields of breaking waves on the slope are obtained by using the tracingmethod.The.numerical results for wave deformation are in good agreement with experimentaldata,and the breaker indexes depending on the kinetic criterion agree approximately with previ-ous results.Furthermore,compared with the experimental results measured by Iwagaki and bythe authors,the tendency of velocity distribution of breaking waves computed by this numericalmethod is also satisfactory.

关键词： MAC method breaking wave Sloping beach wave deformation