太湖风生流及污染物输移扩散数值模拟

建立高精度的太湖三维风生流数值模型和风生流-污染物耦合数值模型，分析了盛行风作用下的太湖风生流特征和风生流驱动下的太湖污染物输移特征。结果表明:稳定后的太湖风生流场，表层流速大于底层流速，表层流向基本上同风向一致，底层流向则与表层大致相反，具有补偿流的特征；风向能显著影响太湖风生流的形态和结构；在垂向扩散作用下，太湖污染物质量浓度沿水深方向上近似均匀分布；在定常风作用下，太湖北部的湖湾区出现多个小尺度闭合环流，不利于污染物的输移扩散，对太湖水环境会产生不利影响。

Numerical simulation of wind-driven current and pollutant transport and diffusion in Taihu Lake

A high-precision 3D numerical model of wind-driven current in Taihu Lake and a coupled numerical model of wind-driven current and pollutant were built. The characteristics of wind-driven current in Taihu Lake were analyzed under prevailing wind condition. Moreover, the characteristics of pollutant transport and diffusion driven by wind-driven current were studied. According to the results, when the wind driven current in Taihu Lake is stable, the surface velocity is significantly higher than the bottom velocity and the surface flow is almost the same as the wind direction while the bottom flow is roughly opposite to the wind direction, which shows the characteristic of compensation current. Wind direction can significantly affect the morphology and structure of the wind-driven current in Taihu Lake. The mass concentration of pollutant in Taihu Lake is approximately evenly distributed along the depth of water under vertical diffusion effect. Under constant wind, several small-scale closed circulations can be found in the bay area of northern Taihu Lake, which is not conducive to the transport and diffusion of pollutants and also has negative effects on the water environment of Taihu Lake.