深水航道整治中新型结构淹没丁坝水流力特性研究

Flow force characteristics of new-type structure submerged spur dike during deep waterway regulation

为研究新型结构淹没丁坝的水流力特性,基于有限体积法与自由液面捕捉法,通过流体计算软件Fluent建立三维数学模型对不同流速、水深与坝长条件下新型结构齿形丁坝的水流力特性进行研究。同时,设计了比尺为1∶50的物理模型对不同坝长条件下新型结构丁坝水流力进行补充验证,数值模拟结果与试验结果符合良好。研究不仅得到了丁坝流场流速与水深的分布规律,同时分析了不同流速、水深与坝长条件下新型结构齿形丁坝的水流力响应规律,进而通过量纲处理分析了相对坝长与淹没度对水流力系数的响应规律,通过独立化分析的方法分别探讨了相对坝长与淹没度对丁坝水流力系数的敏感性。研究成果为新型淹没丁坝在长江南京以下12.5 m深水航道整治工程的应用提供一定的技术支撑与科学指导。

In order to study the flow force characteristics of a new-type submerged spur dike, a 3D mathematical model is developed by using the fluid calculation software Fluent to study the flow force characteristics of the new- type spur dike with tooth-shaped structures under the conditions of different flow velocities, water depths and dike lengths based on the finite volume method and the free surface capture method. Meanwhile, a physical model with the scale of 1 ： 50 is also designed to make a supplementary verification of the flow force of the new spur dike under the conditions of different dike lengths. The numerical simulation results are in good agreement with the model test results. The distribution laws of the flow velocity and water depth of the spur dike＇s flow field are obtained, and the flow force response laws of the new-type spur dike with tooth-shaped structures under the conditions of different flow velocities, water depths and dike lengths are analyzed, and the response laws of relative dike lengths and the critical submergence degree to the flow force coefficients via dimensional process are further analyzed. And the sensitivity of relative dike lengths and the critical submergence degree to the flow force coefficients are respectively discussed by means of independent analysis. The research results will provide certain technical supports and scientific guidance for the location of the new-type submerged spur dikes in the 12.5 m deep waterway regulation works in the lower reaches of the Yangtze River from Nanjing.