徐圩港区邻近海域溢油模拟分析

利用MIKE21水动力模型对徐圩港区附近海域进行潮流数值模拟,并利用实测资料对模型计算的潮位、流速及流向进行验证。验证结果显示:数模结果与实测值吻合较好。该潮流数学模型可以反映研究海域水动力特性,并作为溢油模块的水动力基础数据。基于欧拉-拉格朗日"油粒子"理论考虑油膜运动过程中扩散、蒸发、乳化等过程,建立了徐圩港区邻近海域二维溢油扩散模型,模拟不同潮时情况下发生溢油,考虑不同风况(夏季常风向、冬季常风向和最不利风向),分析不同情况下的溢油油膜漂移路径、漂移路程及扫海面积。结果表明:72 h内油膜最大扫海面积及漂移路程均出现在落潮期最不利风时溢油,分别为28.2 km^2和25.8 km。在夏季常风和最不利风的落潮期发生溢油,油膜会经过口门飘向西北侧海域,对该区域生态环境会造成一定影响。

The oil spill simulation around Xuwei Port Area

The tidal current surrounding Xuwei Port is simulated using MIKE21 hydrodynamic module, and the computed tidal level, current velocity and direction are validated by comparing with observations. It shows that the numerical simulation results agree well with observations. As a result, the tidal current mathematical model could reflect the local hydrodynamic characteristics and can be used as a hydrodynamic base for oil spill model. A two-dimensional oil spill diffusion model around Xuwei Port is established based on the Eulerian-Lagrangian"oil particle"method, which considers the diffusion, evaporation and weathering processes of the oil film. The model is used to simulate oil spill situations in different moments of tide, and to analyze the drift path, drift distance and swept area of oil film under different wind conditions. The results show that both the maximum swept area and drift distance of the oil film within 72 hours occur during the ebb tide under the most unfavorable wind condition, which are 28.2 km^2 and 25.8 km, respectively. The oil film will pass by the entrance of Xuwei Port and drift to the northwest sea area when the oil spill occurs at ebb tide under winter monsoon and the most unfavorable wind condition, which affects the ecological environment in this area.