建筑物影响下的堤坝溃决水流数值模拟方法

采用基于非结构网格的有限体积法对建筑物影响下的堤坝溃决水流进行了数值模拟.为模拟建筑物对溃决水流产生的影响,模型采用了三种方法:固壁边界法、真实地形法和加大糙率法.经物理模型验证,当建筑物顶部不过流时,三种方法均能得到较好的计算结果,其中固壁边界法和真实地形法的计算结果基本一致;而加大糙率法由于对反射波的计算不如其它两种方法灵敏,因而在城区内所得的计算水深比其它方法略低一些.

Numerical modeling of dam-break flow under the influence of buildings

An unstructured finite-volume model was proposed for simulating dam-break and levee-breach water flows under the influence of buildings.The buildings were treated as(1) solid wall boundaries,(2)grid cells with buildings top elevations,and(3) grid cells of larger roughness respectively in the model.Through the verification by flash flood data from a physical model study,all these three approaches show good agreement between measured and calculated results for non-overtopping flow scenarios.Approaches(1) and(2) essentially give the same results while approach(3) leads to a result with a reduced water depth due to its lower sensitivity to the reflection of the flash flood.