The Hydrodynamic And The Sediment Scouring And Silting Numerical Simulation Of The Surrounding Waters Of Haiyang Central Fishing Harbor

The construction of fishing harbor involves the construction of revetment, thesite backfill and the basin degrading, etc. All of this will lead to the change ofcoastline and water depth, thus making the hydrodynamic conditions nearby theproject changed. The change of flow velocity and flow direction will influence thetransport of pollutants and the sediment scouring and silting. Due to the influence ofthese effects is irreversible, choosing the reasonable design is particularly important.These effects can’t be restored once the completion of project, called irreversibleimpacts. Therefore, choosing a reasonable design before the construction of project isparticularly important. Reasonable engineering design requires tiny impact on themarine environment. In this paper, the hydrodynamic and sediment erosion anddeposition numerical simulation researches are applied to the surrounding waters ofHaying Central Fishing Harbor. The reasonable optimal decision is made by analyzingnumerical simulation results. All of these works would provide scientific guidance tothe construction of Haying Central Fishing Harbor.In coastal areas, the water depth is generally shallow. The horizontal scale of tidemovement is much larger than the vertical scale, whereas the hydraulic parameters’change along the vertical direction shows much smaller than the change along thehorizon direction. So depth-averaged models, two dimensional hydrodynamic modeland sediment transport model can be selected for numerical simulation.MIKE21, a series of water dynamics software, developed by the DanishHydraulic Institute（DHI）, belong to two-dimensional free-surface flow model. Sincethe development of MIKE21software in1993, it has been widely applied to solve alarge number of engineering problems, providing theoretical guidance to theconstruction of engineering.In order to study the hydrodynamic conditions and silting and scouring of thesurrounding waters’change due to the construction of Haying Central Fishing Harbor,the two-dimensional hydrodynamic model and sediment transport model are built by MIKE21software. All these works are taking to select the optimum plan, providingtheoretical guidance for the construction of Haying Central Fishing Harbor. The maincontent of the work and conclusions are as follows:1. In this paper, the whole research area is the sea area surrounded by DingziEstuary, Qianliyan, Gulong Mouth and shoreline. Based on the collected water depthand topography statistics, a two-dimensional hydrodynamic model is built byMIKE21software. Some measurement data, such as surface elevation, flow velocityand flow direction at the specified point are used to verify the model. The verificationresults indicate that the model in this thesis is reliable. It is feasible to use this modelfor this project. Then this thesis makes a brief analysis about the flow fieldcharacteristics in the calculation sea area.2. On basis of correct validation of the hydrodynamic model two-dimensionalhydrodynamic models after the construction of the two primary plans are built byMIKE21software respectively. The models simulate the impact on hydrodynamiccondition of the surrounding waters after the construction of project.. By usingnumerical simulation results, this paper analyzes the impact due to hydrodynamicchange. Quantitative analysis is applied to the impact on the hydrodynamic field afterthe construction of two plans. Fifteen representative points are selected out to analyzethe flow velocity. Through the analysis, the flow rate change after the construction ofplan1is less than the other one. It means that the impact on the surrounding waterscaused by the construction of plan1is less than the construction of plan2.3. On basis of the hydrodynamic model, the sediment transport model coupled.The model is built up to simulate the annual seabed topography change with theco-action of wind and current and erosion-deposition after24hours under thecondition of the strong waves wind direction southeast(15m/s) before and after theconstruction of fishing harbor. After the construction of the engineering, no matterwhich plan we choose, the seabed changes of open waters between Haiyang Port andLengjia Village are very small. After the construction of different plans, the differentchange of scouring and silting mainly reflect in the surrounding water of HaiyangCentral Fishing Harbor. 4. Whether annual erosion-deposition trend with the co-action of wave andcurrent or erosion-deposition in one day under the condition of the15meters persecond southeast wind, different levels of deposition occur in the basin interior afterthe construction of two plans. But both would not affect navigation. The differencesmainly reflect on the strengthening scouring of waterways between wharf andshoreline, strengthening scouring of waterways under the port road bridge. Thescouring in the harbor basin after the construction of two plans could not influencenavigation. The differences between two plans mainly reflect on the impact on thestability of port road. As plan1has the east breakwater, making the extent of erosiondecreases near port road, can protect the port road in stable station. Therefore, theresult obtained from sediment transport models is that comparing with plan2, plan1is better.5. By comparation of two plans in hydrodynamic model and sediment transportmodel, the conclusion is that plan1is better than plan2.Based on the numerical simulation of hydrodynamic and scouring and silting, theoptimum plan is selected, providing decision-making for the design of HaiyangCentral Fishing Port.