Effect of large-scale reservoir and river regulation/reclama-tion on saltwater intrusion in Qiantang Estuary

By using field salinity data recorded in the Qiantang Estuary for the nearly forty years (which covers the periods before and after the erection of a large-scale reservoir in the watershed and river regulation/reclamation in the estuary) and one-dimensional salt water intrusion modeling, it is shown that the salt water intrusion decreases caused by increased low water discharge for the reservoir, while the intrusion increases for the increased tidal range because of the river regulation/reclamation. The integrate result is that the saltwater intrusion decreases.     

曹娥江径流特性及其对河口冲淤的影响

曹娥江径流具有浙闽山溪性强潮河口的若干特征,径流年际、年内变幅较大,洪水暴涨暴落,洪枯比极大,年内存在两个汛期,即梅汛期和台风汛期. 根据曹娥江径流特性,本文讨论了曹娥江河口河床洪冲枯淤变化特性,径流对潮汐大小的间接影响以及径流对曹娥江口门外主槽出口方向的影响.     

天然弯曲河流的三维数值模拟

对Cartesian坐标系下的RANS方程进行三维$\xi$-$\eta$-$\zeta$坐标变换，建 立了非正交三维曲线坐标下弯曲河流的标准$k$-$\varepsilon$湍流模型. 对自由水面 的模拟采用``改进的刚盖假定'，河床和岸壁阻力的模拟采用壁面函数方法. 模型通 过具有实验数据的实验室连续弯曲水槽进行验证，模拟的流速值与实验数 据吻合良好，将模型应用于天然连续弯曲河流的流场计算，给出了表层和底层流速 矢量场和11个断面二次环流矢量图，显示该模型具有模拟天然弯曲河流的能力.