采用平面二维水动力及污染物输运模型,针对研究海域的水动力特性,应用潮流场作为背景场驱动控制污染物浓度的对流扩散方程,利用有限元方法对苏北辐射沙洲海域大、中、小潮水动力特征及如东洋口港附近污染物输运进行了计算分析。计算结果与实测结果比较表明:计算所得潮流场合理,辐射沙洲区部分潮流脊间水道的潮流运动具有明显的定向往复流形式,潮流强,潮差大,且形成了辐射状潮流流场;排污口排放的污染物的扩散影响范围不大,不利潮型为小潮,大潮和中潮情况下,污染面积有所减小。
A finite element method for the numerical simulation of the dilution and diffusion of the sewage outlet near Yangkougang is considered in this paper. Based on the computed tidal current field, the distributions of COD concentration near south coast of north Jiangsu were simulated. Comparison between computation results and the observed data indicates that this model can reasonably simulate the tidal current, tidal currents in part of waterways which are in sandbank ridges obviously have to-and-fro movement, and strong tidal current and great tidal range occur; the range of contamination diffusion derived from sewage outlet is very limited, and the influence range of sewage comes to the maximum when ebb slacks in neap tide period.