The Impact Of Wave Farm To The Erosion And Siltation In The Bay

Wave energy is one of the most promising renewable energy resources in the world. However, our country still in the primary stage of the exploitation of wave energy resources. The exploitation of wave energy will result in the changes of hydrodynamic nearshore, and it will bring some problems to engineering of nearshore. So, it’s very significant to study the change of hydrodynamics of nearshore before the wave energy convert devices are setted. This paper study the changes of wave climate, hydrodynamic and sediment transport due to the installing of wave energy convert devices. The research was based on Zhangjiabu area in WeiHai city of ShanDong peninsula. And, this paper can be divided into three parts:First of all, the third generation wave model SWAN is used to simulating the wave climate of ShanDong peninsula and the modeled data are compared with the observed value. The result show that the modeled are validated with buoy data. Then, the wave energy resources of ShanDong peninsula were calculated, and the wave energy resources of Zhangjiabu area were statics. Last, an experiment was used to study the absorbing rate of wave by WEC(wave energy convert device). And,numerical model, the Boussinesq equation, was used to study the wave evolution after the experiment device. In the experiment, two cases was set up.The wave height of case1and case2are0.0625m,0.25m, respectively. The result show that when the wave device absorption rate up to45%, the modeled data of casel validated well with the observed value,and when the absorption is15percent in case2,the result is fitting better.Secondly, SWAN model was used to study the wave climate change of10m depth, which was induced by the install of WEC in Zhangjiabu area. In the paper, two direction was used, they are S and SE, and five kinds of absorption rate were used, they are20%,40%,60%,80%,100%, to research the effect of different direction and absorption to the wave climate change in nearshore.The result show that wave changes nearshore increase gradually along with the absorption rate. At the same time,location of the wave energy devices effect the wave changes as well,the far the smaller,as well as the wave incoming direction.Finally, HD module and MT module was used to simulation the hydrodynamic condition and sediment transport of Zhangjiabu area. Then wave induced current and bed shear stress are study in spring, summer and autumn. Then the wave induced current and sediment transport after setting up the WEC were compared with the data of no WEC. In this paper,100%absorption rata was used to study the maximum influence by WEC. The results show that:wave energy devices influence the hydrodynamic mainly through the wave, as shallow the influence as large. In a word, they have little influence on the longtime scour-silt of nearshore.