河道、滞洪区洪水演进数学模型

Numerical Model of Flood Propagation of Rivers and Flood Detention Basin

采用有限体积法建立了适应河道、滞洪区复杂情况的洪水演进一、二维衔接数学模型.构造了适合河道洪水计算的一、二维河道型网格和滞洪区二维地面型网格,网格具有多点、多面,既镶嵌又衔接的特点.阻水建筑物对洪水演进速度影响较大,所以,将其模化成特殊通道,提出了洪水演进过程中渗流所造成的水体损失的计算模式.将该模型应用于大清河滞洪区,讨论了洪水边界条件,确定了模型糙率,率定了模型渗流参数.结合大清河"96.8实测洪水资料"进行了洪水演进数值模拟,分别对河道的水位、流量和滞洪区来水时间进行了模型验证,验证结果基本吻合.

The 1D and 2D numerical combination model adapted to the complicated situation of flood propagation of rivers and flood detention area was built by finite volume method （FVM） .The model grids included the river grid and ground grid, which connected each other point to point and face to face. By modeling blocking building to special channel, the numerical mode for the water loss of seepage was suggested. The model was applied to Daqinghe detention basin, in which flood boundary conditions were discussed, the roughness of model was confirmed, and seepage coefficient was rated. The propagation of the diversion flood in Daqinghe detention basin in August, 1996 was simulated successfully and the model verification results were satisfactory, which contained the verification results of water level, flow in rivers and water reaching time in detention basin.