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Numerical tidal current Modeling Using Fine Boundary-Fitted Grids for tidal Flats

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China Ocean Engineering 1999年第2期14卷 115-124页

作者： Shi, FY Ding, PX Kong, YZ E China Normal Univ State Key Lab Estuarine & Coastal Res Shanghai 200062 Peoples R China

Fine grids with small spacing in boundary-fitted coordinates are normally used to treat the computation of fluid dynamics for estuarine areas and tidal flats. However, the adoption of Cartesian components of velocity vectors in this kind of non-orthogonal coordinates will definitely result in a difficulty in solving implicitly the transformed momentum equations, and also complicate the wet-dry point judgement used for flood areas. To solve this problem, equations in terms of generalized contravariant velocity vectors in curvilinear coordinates are derived in the present study, by virtue of which, an Alternative-Direction-Implicit numerical scheme in non-orthogonal grids would then be easily obtained, and wet-dry point judgement would as well be largely simplified. A comparison is made between the explicit scheme and implicit scheme, showing that the present model is accurate and numerically stable for computations of fluid dynamics for estuarine areas and tidal flats.

关键词： tidal flat estuary boundary-fitted grid tidal current numerical model

Coastline changes and tidal current responses due to the large-scale reclamations in the Bohai Bay

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Journal of Oceanology and Limnology 2023年第6期41卷 2045-2059页

作者： Zhe HUANG Haijue XU Yuchuan BAI Fengshuo SHI Zhichao WEN State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300350China Institute for Sedimentation on River and Coastal Engineering Tianjin UniversityTianjin 300350China

China’s Bohai Bay has experienced large-scale land reclamation since *** reclamation projects create a nearshore ecological imbalance and shift sediment transport by changing the tidal ***,these tidal current changes are not comprehensively *** this paper,the coastline changes in Bohai Bay due to reclamation are investigated and the responses of the tidal current are calculated through numerical *** results show that the coastline length of the bay increases by more than 500 km from 2000 to 2015 with the largest reclamation rate of 150.9 km^(2)/***,the current velocity changes with an uneven distribution near the reclamation due to construction masking and dike *** tidal symmetry also changes in most nearshore areas,with opposite variations in the current velocity at peak flood and ebb *** addition,the tide direction deflects to bypass the reclamation and is usually consistent with the *** analysis of the dominant M2 tidal constituent shows that the range of the reciprocating current is widely *** total influence of the reclamation can reach the-8-m isobaths in Bohai *** in the tidal current are the main causes of water environment ***,the arrangement and structural optimization of reclamation projects should be considered in the future.

关键词： Bohai Bay reclamation coastline tidal current

Two-Dimensional Mathematical Model of tidal current and Sediment for Oujiang Estuary and Wenzhou Bay

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China Ocean Engineering 2002年第1期17卷 107-122页

作者：陆永军李浩麟董壮陆建宇郝嘉凌 River and Harbor Department Nanjing Hydraulic Research Institute

A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the Wenzhou Bay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport are presented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with their initial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of the critical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested. The model verification computation shows that, the tidal levels computed from the model are in good agreement with the field data at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measured along the totally 52 synchronously observed verticals distributed over 8 cross sections. The coraputed tidal water throughputs through the Huangda'ao cross section are close to the measured data. And the computed values of bed deformation from Yangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992. The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of the reclamation project on the Wenzhou shoal are predicted by means of this model.

关键词： mathematical model tidal current non-uniform suspended load non-uniform bed load non-equilibrium transport bed deformation

Corrected Formula of Bed Resistance Coefficient for Plane Numerical Simulation of tidal current

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China Ocean Engineering 2000年第2期15卷 221-227页

作者：宋志尧刘一凡 Coll. Harbor Waterway/Coast. Eng. Hohai University Nanjing 210098 China Dept. of Comp. Sci. and Technology Nanjing Univ. Post/Telecommunication Nanjing 210003 China

By means of a logarithm law for the velocity profile, a corrected formula of bed resistance coefficient, which involves many factors such as gradient of still water depth, variation of surface elevation, flow direction, and so on, is derived from the 3D governing equations of tidal current by averaging over the whole water depth. Theoretical analysis and application have shown that the 2D plane tidal current numerical model would be more reasonable and could be applied to steep bottom topography when the corrected bed resistance coefficient is used, therefore the results of reproduction simulation and engineering calculation would be more scientific and reasonable.

关键词： tidal current bed resistance coefficient numerical simulation corrected formula

Experimental Study on Local Scour Around Bridge Piers in tidal current

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海洋工程：英文版 2004年第4期18卷 669-676页

作者：韩玉芳陈志昌 Nanjing Hydraulic Research Institute Nanjing 210029 China

Local scour around a bridge pier is an important parameter for the design of a bridge. Compared with the local scour in a mono-directional current, the local scour in a tidal current has its unique characteristics. In this paper, several aspects of local scour around bridge piers in tidal current, including the scour development process, the plane form of a scour hole and the maximum scour depth, are studied through movable bed flume experiments.

关键词： bridge pier local scour tidal current

An Application of Finite Volume WENO Schemeto Numerical Modeling of tidal current

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China Ocean Engineering 2006年第4期20卷 545-556页

作者：杨中华槐文信曾小辉 State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University The Second Investigation and Design Institute of China Transportation Engineering

A depth-averaged 2-D numerical model for unsteady tidal flow in estuaries is established by use of the finite volume WENO scheme which maintains both uniform high order accuracy and an essentially non-oscillatory shock transition on unstructured triangular grid. The third order TVD Range-Kutta method is used for time discretization. The model has been firstly tested against four cases： 1） tidal forcing, 2） seiche oscillation, 3） wind setup in a closed bay, and 4） onedimensional dam-break water flow. The results obtained in the present study compare well with those obtained from the corresponding analytic solutions idealized for the above four cases. The model is then applied to the simulation of tidal circulation in the Yangpu Bay, and detailed model calibration and verification have been conducted with measured tidal current in the spring tide, middle tide, and neap tide. The overall performance of the model is in qualitative agreement with the data observed in 2005, and it can be used to calculate the flow in estuaries and coastal waters.

关键词： tidal current numerical modeling WENO scheme unstructured triangular grid

Numerical modeling of tidal current of LNG terminal in Caofeidian,Bohai Sea

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Journal of Southeast University(English Edition) 2009年第1期25卷 108-112页

作者：廖鹏张玮东南大学交通学院南京210096 河海大学交通学院南京210098

In order to reasonably simulate tidal currents around small structures such as piles in a large-scale model domain, a 2-D hydrodynamic integrated model for Bohai Sea is established with the finite element method. The grid can be discretionarily refined as a non-structure triangle or quadrilateral so that piers can be treated as one or several impermeable elements with an area of 20 to 30 km^2 in a model domain over 85 700 km^2. The computational results of tidal levels and horizontal velocities are in good agreement with the field data. Based on the computed results by the model, the layout of an open 105 DWT liquefied natural gas （LNG）terminal in Caofeidian, Bohal Sea is effectively and reasonably optimized. It can be concluded that the model is suitable and reasonable for direct simulation of tidal currents around small structures in projects.

关键词： tidal current numerical model pier Bohai Sea

A combined numerical model of three-dimensional tidal motion and sediment transport in tidal current and its application

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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 300072, China 2. Department of Hydraulics, Tianjin University, Tianjin 300072, 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

Numerical simulation of fluctuation and undulation of the thermo-cline under tide (tidal current) action in the Bohai Sea

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Acta Oceanologica Sinica 1993年第3期12卷 347-357页

作者： Zhang Yanting and Wang Yijiao First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China

Besides seasonal variation, instantaneous variation of thermal layer will occur under the effects of tide, tidal current and wind disturbance. In this study the numerical simulation has been first carried out on fluctuation and undulation of thermal layer under influence of tide (simultaneous input of 8 tidal components). The study reveals the geographic distribution of thermal layer fluctuation in the entire study region and temporal and spatial variations of the undulation in tidal period superposing on the fluctuation. Especially, the wave with large amplitude simulated is consistent with observation in the channal and the sea areas with a convex coastline and complex variation of depth, internal relations of tide, tidal current, residual current as well as the factors such as geography, and the fluctuation of thermal layer is induced by residual current due to unsymmetry which occurs as a result of the tidal movement in lower layer influenced by friction and geography, meanwhile, analysis indicates that the fluctuation of thermal layer and tidal oscillation are different undulations in character.

关键词： line In action in the Bohai Sea Numerical simulation of fluctuation and undulation of the thermo-cline under tide tidal current