基于水动力耦合模型的平原地区排涝规划

Drainage planning for plain areas based on coupled hydrodynamic model

针对滨海平原感潮河网地区水系流态复杂、受边界条件和工程调度影响显著的特点,遵循充分发掘水系调蓄能力、多闸联调和水闸优先抢排的原则,对感潮河网和湖泊分别构建一维和二维水动力数学模型,利用2种模型模拟水位、流量相等的条件,对一维和二维水动力数学模型进行耦合.以辽东湾新区水系排涝规划为例,对4种设计方案进行了分析对比,得出了河道断面和排涝闸门规模.结果表明:方案一和方案二中,河道断面尺寸不变时,排涝闸门规模偏小,造成上游水位偏高;方案三和方案四中,排涝闸门规模不变时,扩大河道断面尺寸对域内水位影响不大.从排涝能力和经济等角度综合考虑,选取方案四为最优方案.计算结果较好地反映了滨海平原感潮河网地区河道断面尺寸和排涝闸门规模对排涝能力的影响,可为区域工程设计和制定排涝方案提供技术保障.

In the coastal plain tidal river network with a main feature of a complicated flow pattern which is highly influenced by the boundary condition and reservoir regulation,1D and 2D hydrodynamic modeling were established for the river network and the lake area,respectively,based on the ground rules of reservoirs storage capacity,multi-reservoir jointly operation and priority gate operation.The important principle of model coupling is that water level and discharge simulated by 1D and 2D model are equal respectively at the junction section.Taking the drainage planning in Liaodong Bay Area for example,four schemes were analyzed and the optimal size of the flood drainage gate and river cross-section were achieved.The results show that when the river cross-section remains unchanged in Scheme Ⅰ and Scheme Ⅱ,the small-size flood drainage gate leads to the higher water level of the upstream.The enlargement of river cross-section has little effect on the water level when the size of flood drainage gate remains unchanged in Scheme Ⅲ and Scheme IV.Considering the perspective of drainage capacity and economic point of view,Scheme IV can be found as the optimal scheme.Obviously,the results could provide a technical support and reference for the local project design and the developing of the drainage planning.