淹没丁坝群二维水流数值模拟新方法

为模拟淹没丁坝群平面二维水流运动，提出了淹没丁坝群二维水流数值模拟新方法并建立了数学模型。新方法的主要实施方案:① 将丁坝视为无厚度坝，用网格线概化丁坝；② 采用新的网格节点布置形式，即水深、流速节点布置于网格界面上，水位节点布置于网格中心，有别于一般交错网格节点布置。模型采用基于结构网格下的有限体积法对方程组进行离散，同时将淹没丁坝坝顶水深代入离散方程中进行求解。采用已有的水槽试验资料，进行了初步验证，模拟了长江下游东流水道已建丁坝群工程实施后河道的流场和水位场，结果表明计算和实测符合较好。

A new numerical simulation approach for 2-D flow with submerged spur-dikes

A new two-dimensional numerical model is presented to simulate the flow in the vicinity of submerged spur-dikes, which employs a finite volume method based on structured triangular mesh, and considers water depth around dikes in continuity and momentum discrete equations. In this model, the spur-dikes are supposed as the dikes without thickness, and generalized as grid lines; the depth and velocity nodes are arranged in grid interface, and the water level nodes are arranged in grid center, which is different from the general staggered-grid nodes distribution. The model is first validated against the available observed data obtained from a flume experiment. It is then applied to simulate the flow with submerged spur-dikes in Dongliu waterway downstream the Yangtze River. The model predictions generally agreed with measured data including velocity and water depth, which demonstrates the capability of the model to simulate the flow in the field of submerged spur-dikes.