淀北蓄滞洪区洪水模型及局部冲刷特性的研究

Research on Flood Mathematical Model and Local Scouring Characteristics in Dianbei Basin

以天津市淀北蓄滞洪区为例,采用有限体积法剖分网格、建立泛区洪水演进数学模型,模拟塔基工程建设前后泛区的洪水演进进程。通过数值模拟分析工程建设对蓄洪过程的影响;构建工程局部加密网格模型,计算工程建设前后水力条件的变化量,分析电塔基础桩柱对局部行洪的影响,并采用局部冲刷公式估算局部加密模型冲刷深度。结果显示塔基工程建设后,不会明显影响淀北蓄滞洪区的总体洪水演进过程,对局部行洪影响也较小,所以在此蓄滞洪区建立塔基工程是可行的。

A mathematical model on the hasis of the finite volume is established in Dianhei Basin. The process of flood routing and the corresponding flow field are simulated before and after the construction of the project. The project＇s impacts on the overall water level and water depth in the basin are compared and analyzed. The variation of water level, water depth and velocity on feature points near the pile foundation are calculated and the effects on flood storage with numerical simulation are analyzed. This paper focuses on establishing partial encryption model, simulating the distribution of velocity change and water level fluctuation,investigating the effects of tower foundations on local flooding and estimating local souring depth of encryption model. Results show that the project has an impact on overall and local flood routing process in Dianhei Basin, but the effect is not significant. So the project is feasible.