鸭绿江公路大桥溢油漂移扩散三维数值模拟

应用三维河口海岸海洋数值模式ECOM-si,加入油膜计算模块,模拟在鸭绿江公路大桥主跨航道处溢油事故(溢油量为100 t)发生后油膜的漂移扩散.模拟结果显示,夏季溢油事故发生后油膜分别于0.9h、1.5h后到达四道沟取水口和丹东造纸厂取水口,持续影响时间分别为0.6h和1.7h;冬季溢油事故发生后油膜分别于1.2h、1.7h后到达两地取水口,持续影响时间分别为0.6h和2.5h.冬夏季,油膜均没有到达燕窝取水口.鸭绿江夏季径流量远比冬季径流量大,但涨潮期间油膜上溯距离反而更远.数值试验结果表明,夏季较强的涨潮流是该现象的次要原因,风是首要原因.鸭绿江大桥上游河道先是西北走向,导致冬季西北风阻碍油膜向上游漂移,然后是近南北走向,导致夏季南风促进油膜向上游漂移.

Three-dimensional numerical simulation of the drift and diffusion of oil film at the highway bridge in the Yalu River

An improved 3D numerical model ECOM-si, coupled with the drift and diffusion module of oil film, was adopted to simulate the thickness and trace of the oil film after an oil spill accident (100 tons leakage) is occurred at the main pier of the highway bridge in the Yalu River. The model results show that the oil film reaches the water intakes of Sidaogou and Dandong Paper Mill at 0.9 h and 1.5 h after the oil spill, experiencing duration of 0.6 h and 1.7 h in summer, respectively. The oil film reaches the two places at 1.2 h and 1.7 h after the oil spill, experiencing duration of 0.6 h and 2.5 h in winter, respectively. No matter in summer or in winter, the oil film will not reach the water intake of Yanwo. Although the river discharge in summer is much larger than the one in winter, the oil film drifts upstream farther in summer than in winter during flood current. The numerical experiment results show that the stronger flood current in summer is only the second reason for the pheonomena, while the wind is its principal reason. The orientation of the river is north-west near upstream the bridge which results in the oil film blocked by the northwest wind in winter, and is almost north-south farer upstream the bridge which results in the oil film pushed forward by the south wind in summer.