冀东南堡人工岛工程潮流泥沙数值模拟*

采用平面二维潮流、泥沙数学模型,结合三重嵌套网格模式,就冀东南堡人工岛附近海域的潮流及泥沙场进行模拟。人工岛工程前、后的潮流场变化表明:由于人工岛及引桥对水流的拦截作用,人工岛后沿及引桥两侧流速减小,人工岛前沿则随着过水断面束窄,流速有所增大。同时,在挖沙池附近,由于局部地形调整,水动力条件在不同位置变化情况稍有差异。此外,泥沙冲淤演变验证了水动力条件变化对泥沙输移的影响:在水流流速增大的区域发生冲刷,而在水流动力减弱的区域则发生淤积。

Flow and sediment numerical simulation on artificial island of south fort in eastern Hebei province

A 2-D mathematical model with multiple nested grids of tidal current and sediment in estuary was set up. With the help of this model, the flow and sediment transport field near the artificial island of south fort in eastern Hebei province was simulated. It was concluded from the flow field simulation that the current velocity decreased at the back of the island and at each side of the approach bridge as a result of their interception effect,and increased in front of the island for its deflecting effect. In addition, the hydrodynamic conditions at different part of the sand digging pools also revealed various characteristics because of the changes of topography. The results of the simulation of sediment field coincided with the influence of hydrodynamic conditions change on sedimentation: siltation happened where flow strength decreases, while erosion happened where flow strength increases.