长江上游洛碛航道采砂坑三维水温结构模拟研究

3D numerical simulation for water temperature in sand mining pit in Luoqi waterway of Upper Yangtze River

采砂坑是航道整治中经常会遇到的一个问题,它的存在不利于航道运输,同时也对鱼类生存有着一定影响。利用MIKE 3软件的水动力模块对夏季及冬季工况下的长江上游航道洛碛采砂坑区域三维水温结构进行模拟,取采砂坑两监测点模拟数值与实测数据验证了模型的可靠性。取邻近区域非采砂坑两环境数据点分析其水温结构,同时将采砂坑环境与非采砂坑环境的模拟结果进行对比分析,以探究它们水温结构的异同。结果表明:垂向上采砂坑内水温随水深变化不大,温度数值较为恒定,冬季工况下平面上采砂坑水体水温比非采砂坑水体更高,夏季工况则较低。该模型能够较好地模拟出采砂坑内水温的变化过程及变化趋势,具有较好的实用性和有效性。研究成果可为航道整治的方案选择及长江鱼类的生境保护提供一定的参考。

Sand mining pit is a common problem in waterway regulation,which is not only adverse to waterway transportation,but also has a certain impact on fish habitat.In this paper,the 3D water temperature structure of mining pit area in the Luoqi waterway was simulated by using the hydrodynamic module of MIKE 3 software under summer and winter condition.The reliability of this model was verified by measured data at two monitoring points in the sand mining pit.The temperatures in non-sand mining pits of adjacent area were simulated,and its water temperature structure was analyzed.At the same time,the simulation results of the sand mining pit environment and the non-sand mining pit environment were compared and analyzed to explore the similarities and differences of their water temperature structure.The results showed that the water temperature in vertical profile changed little in the sand mining pit,almost a constant.In the plane,the water temperature in the sand mining pit was higher than that in the non-sand mining pit in winter,and it was lower in summer.This model can well simulate the change process and trend of water temperature in sand mining pits,and has good practicability and effectiveness.The research results can provide certain reference for the selection of waterway regulation scheme and the fish habitat protection in the Yangtze River.