生态修复后普兰店湾水体交换数值研究

本文基于非结构化数值模型研究了普兰店湾的水动力特征，耦合输移扩散模型研究不同修复方案对水交换的影响。模拟得到:普兰店湾内涨落潮流向与岸线走向一致，池梗拆除增加15%的水域面积，提升了10%的海湾纳潮量。方案一工程后池梗高程较低，滩涂漫滩及干出流场较为均匀；方案二工程后池梗相对较高，池梗之间流速较大，滩涂流场较为杂乱。工程前湾中水体半交换时间为0～70天左右，湾底区域在70天以上，方案一工程实施后，湾中半交换时间降至50天，方案二降至60天；工程前湾内平均半交换时间为36.8天，方案一下降至 24.0天，方案二降至 28.5天，方案一较方案二提升12%，对湾内水质改善更为明显。

Numerical simulation of water exchange changes in Pulandian bay after ecological restoration

The hydrodynamic characteristics of Pulandian bay was studied based on the unstructured numerical model, the influence of different removal elevation of pool stem on water exchange was studied coupling the transport and diffusion model. The result showed: the direction of fluctuations in Pulandian bay was basically the same as that of the shoreline, after the pool stem was removed, the water area would increase by 15% and bay tidal volume would increase by 10%. When the elevation of pool stem was low in plan 1, the flood and dry-out flow was more uniform on intertidal zone; when the pool stem remained too high in plan 2, the flow velocity between the pool stems were large, and the tidal current field was chaotic. Before the project, the water half-exchange time of water in the bay gradually increased from 0 d to 70 d, and above 70 d at the bottom. After the project, the maximum half-exchange time in the bay of plan 1 was reduced to 50 d, and reduced to 60 d in plan 2. The average half-exchange time in the bay was 36.8 days, which dropped to 24.0 days after the implementation of plan 1, and 28.5 days for plan 2, the water quality improvement of plan 1 is 12% higher than plan 2.