Quantitative Study of Groundwater Flow and Solute Transport in Karst Aquifers     

Bill X. HU 《《地质学报》英文版》2013,87(Z1):636-636

  相似文献   

Nonlinear effect on inertia component of wave forces on a cylinder     

Li Yanbao  Song Reng 《海洋学报(英文版)》1995,14(3):429-437

Ｎｏｎｌｉｎｅａｒｅｆｆｅｃｔｏｎｉｎｅｒｔｉａｃｏｍｐｏｎｅｎｔｏｆｗａｖｅｆｏｒｃｅｓｏｎａｃｙｌｉｎｄｅｒ￥ＬｉＹａｎｂａｏａｎｄＳｏｎｇＲｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＨｙｄｒａｕｌｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉ...  相似文献   

Nonlinear modeling of liquid sloshing in a moving rectangular tank   总被引：2，自引：0，他引：2  

M. Serdar Celebi  Hakan Akyildiz 《Ocean Engineering》2002,29(12):834-1553

A nonlinear liquid sloshing inside a partially filled rectangular tank has been investigated. The fluid is assumed to be homogeneous, isotropic, viscous, Newtonian and exhibit only limited compressibility. The tank is forced to move harmonically along a vertical curve with rolling motion to simulate the actual tank excitation. The volume of fluid technique is used to track the free surface. The model solves the complete Navier–Stokes equations in primitive variables by use of the finite difference approximations. At each time step, a donor–acceptor method is used to transport the volume of fluid function and hence the locations of the free surface. In order to assess the accuracy of the method used, computations are verified through convergence tests and compared with the theoretical solutions and experimental results.  相似文献   

Optimum fifth order Stokes wave theory   总被引：1，自引：0，他引：1  

Fu Yuhua 《海洋学报(英文版)》1995,14(1):91-101

ＯｐｔｉｍｕｍｆｉｆｔｈｏｒｄｅｒＳｔｏｋｅｓｗａｖｅｔｈｅｏｒｙ￥ＦｕＹｕｈｕａ（ＣｈｉｎａＯｆｆｓｈｏｒｅＯｉｌＤｅｖｅｌｏｐｍｅｎｔ＆ＥｎｇｉｎｅｅｒｉｎｇＣｏｒｐｏｒａｔｉｏｎ，Ｐ．Ｏ．Ｂｏｘ４７０９，Ｂｅｉｊｉｎｇ１０００２７，Ｃｈｉｎａ）...  相似文献   

Fixed-frequency Stokes wave expansion     

Hsien-Kuo Chang  Jin-Cheng Liou 《Ocean Engineering》2006,33(3-4):417-424

The study describes a new fixed-frequency Stokes wave theory that differs from previous Stokes wave theories that fix the wave number. The present wave expansion analytically reveals that the wavelength increases with wave height and exceeds than the wavelength obtained by linear wave theory. A method proposed to comparably transform the wave celerity of Fenton's [Fenton, J.D., 1985. A fifth-order Stokes theory for steady waves. Journal of Waterway, Port, Coastal and Ocean Engineering 111, 216–234.] wave theory to the present one. A direct calculation of the wavelength is introduced for practical solutions, avoiding the need to solve a nonlinear equation using an iterative numerical method.  相似文献   

Mass transport in a two-layer wave boundary layer     

Chiu-On Ng   《Ocean Engineering》2001,28(10):1731

The transport of a chemical species under the pure action of surface progressive waves in the benthic boundary layer which is loaded with dense suspended sediments is studied theoretically. The flow structure of the boundary layer is approximated by that of a two-layer Stokes boundary layer with a sharp interface between clear water and a heavy fluid. The simplest model of constant eddy diffusivities is adopted and the exchange of matter with the bed is ignored. For a thin layer of heavy fluid, whose thickness is comparable to the surface wave amplitude and the Stokes boundary layer thickness, effective transport equations are deduced using an averaging technique based on the method of homogenization. The effective advection velocity is found to be equal to the depth-averaged mass transport velocity, while the dispersion coefficient can be shown to be positive definite. Explicit expressions for the transport coefficients are obtained as functions of fluid properties and flow kinematics. Physical discussions on their relations are also presented.  相似文献   

大尺度海工圆柱的非线性波浪载荷     

黄华  罗志高  孙明光  张经汉  黎辉 《热带海洋学报》1999,(4)

引入Stokes二阶水波理论,建立了对海洋工程中大尺度综合型圆柱式结构波浪载荷的二阶修正统一积分算式。通过对波势特征解法的推广及引入干扰波叠加法、最小二乘法,使原仅适合于轴对称单柱的二阶散射波浪载荷快速积分算法可完全适用于类型广泛的任意型实用圆柱的计算。几则实例(圆台,单、双柱)的计算检验了该方法的有效性。  相似文献   

基于实测重力异常和地形数据确定重力梯度的研究          下载免费PDF全文

刘金钊  柳林涛  梁星辉  叶周润  苏晓庆 《地球物理学报》2013,56(7):2245-2256

本文利用澳大利亚北领地West Arnhem Land 地区实测重力异常数据并联合DEM(9")和SRTM3(3")地形高程数据,使用移去-恢复技术和Stokes积分方法计算了该地区两条剖面的重力梯度及其功率谱密度,使用FFT方法解算了整个地区的重力梯度值,结果证明了联合重力异常数据和高分辨率地形高程数据能有效地提高重力梯度的解算精度;功率谱密度的计算结果与国外成熟的重力梯度功率谱密度模型相吻合,表明高于0.3 Hz频率范围的功率谱密度可看做噪声,为重力梯度数据处理中噪声的辨别和剔除提供了借鉴,另外对重力梯度辅助导航基准图的构建以及重力梯度测量系统的标定提供了有益的探索.  相似文献   

Effect of Stokes drift on upper ocean mixing   总被引：1，自引：0，他引：1  

LI Shuang  SONG Jinbao  SUN Qun 《海洋学报(英文版)》2008,27(2):11-20

Stokes drift is the main source of vertical vorticity in the ocean mixed layer. In the ways of Coriolis - Stokes forcing and Langmuir circulations, Stokes drift can substantially affect the whole mixed layer. A modified Mellor-Yamada 2. 5 level turbulence closure model is used to parameterize its effect on upper ocean mixing conventionally. Results show that comparing surface heating with wave breaking, Stokes drift plays the most important role in the entire ocean mixed layer, especially in the subsurface layer. As expected, Stokes drift elevates both the dissipation rate and the turbulence energy in the upper ocean mixing. Also, ilffluence of the surface heating, wave breaking and wind speed on Stokes drift is investigated respectively. Research shows that it is significant and important to assessing the Stokes drift into ocean mixed layer studying. The laboratory observations are supporting numerical experiments quantitatively.  相似文献   

Hydrodynamic modelling for groundwater flow through permeable reactive barriers     

Diganta Bhusan Das 《水文研究》2002,16(17):3393-3418

Hydrodynamic modelling for analysis of groundwater flow through permeable reactive barriers (PRBs) is addressed in this paper. Permeable reactive barriers constitute an emerging technology for in situ remediation of groundwater contamination and have many advantages over the traditional ex situ treatment methods. The transport domains during groundwater flow through PRBs often may involve free‐flow or non‐porous sections. To model the fluid mobility efficiently in such situations, the free and porous flow zones (PRBs) must be studied in conjunction with each other. The present paper is devoted to the analysis of groundwater flow through combined free flow domains and PRBs. The free‐flow regime is modelled using the Navier–Stokes equations whereas the permeable barriers are simulated by either the Darcy or the Brinkman equation. In order to couple the governing equations of motions, well‐posed mathematical formulations of matching boundary conditions are prescribed at the interface between the free‐groundwater‐flow zones and the permeable barriers. Combination of the Navier–Stokes equations with the Brinkman equation is more straightforward owing to their analogous forms. However, the Navier–Stokes and Darcy equations are incompatible mathematically and cannot be linked directly. The problem is resolved in this paper by invoking validated hydrodynamical expressions for describing the flow behaviour at the interfaces between free‐flow and porous zones. Three schemes for the analyses of fluid flow in combined domains are applied to the case of groundwater flow through permeable reactive barriers and different model results are compared. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献