The Application Of Tidal Flow Mathematical Model In The Offshore Marine Area Environmental Functional Zoning Adjustment

The offshore marine area is the valuable marine resources of the earth, it is vital to explore and utilize the marine resources for human, which is also the extremely active and dense region of exploring the ocean for human. With the development of human society, the exploration of the offshore marine area is accelerated. However, the exploration of offshore marine area is restricted by the functional zoning. The appropriate adjustments should be carried out according to the environmental function zoning principle that local interests subordinate to the general interests. The environmental resources of the offshore marine area must be protected meanwhile the need of economic development is satisfied, the unification of the environmental protection, economic and social development is also done. Before the offshore marine area environmental functional zoning adjustment scheme is made, the planed offshore marine area information such as the natural environment condition, the quality status of seawater and the data of the pollutants into the sea should be comprehensive collected, and based on the data information, the self purification capacity of the offshore marine area is analyzed, the simulate calculation of pollutants is made, the change regularity of the seawater quality variation is analyzed, the boundary of he regional adjustment is determined. The adjusting boundary of the environmental function zoning in the offshore marine area in order to be reasonably determined, it is crucial that the study of the mathematical model in the offshore marine area should be carried out.The main goal of the thesis was that the tidal flow mathematical model in the offshore marine area was suitable constructed, and the model was applied in the Haiyanghong port, which could solve the problem that the environmental function zoning adjustment in the offshore marine area and the sewage outfall selection. Taken the environmental function zoning adjustment in the offshore marine area of Haiyanghong port as an example, the model was established. On the basis of the motion law of tidal flow near the port was simulated by numerical calculation, the effect on the tidal flow movement was predicted after the construction of the Haiyanghong port, the diffusion concentration of the pollutants(COD、 NH3-N、petroleum)into the sea at the different sewage outfall location was predicted, the adjustment range of the environmental function zoning in the offshore marine area was determined, the different sewage outfall location effect on the planed emission sea area was analyzed, the reasonable suggestion on the determination of the sewage outfall optimum location was put forward.The pollutants diffusion in the Haiyanghong port was predicted by the application of the ADI numerical model, the adjustment range of the environmental function zoning in the offshore marine area was determined, which was the sea constructing area of Haiyanghong port, the port nearby and the port in the sea which covered 108 square kilometers were included. The concentration that the above three kinds of pollution factors from the sewage outfall 200m was estimated by the method which the calculation formula of point source diffusion and the numerical calculation result were combined. The results showed that, COD from the sewage outfall within 50m over the second standard of the national water quality standard, NH3-N from the sewage outfall 150m over the second standard of the national water quality standard, the petroleum over the second standard of the national water quality standard, but no more than the fourth standard of the national water quality standard. The highest concentration appearance at the moment of the sea tide surged, the lowest concentration appearance at the moment of the sea tide fell. The pollutant concentration diffusion range and intensity of the different sewage outfall locations was compared in the thesis, the proper sewage outfall location which between 1#、2# source was determined. The adverse selection of the sewage outfall caused harm to the environment was avoided by simulated predictionThe numerical simulated results and the physical model experimental results were compared and analyzed, both of them were in good agreement. Therefore, it was feasible that two-dimensional numerical simulation of tidal flow field in the offshore marine area based on the ADI numerical model.