天然连续弯道中水流运动的三维数值模拟

3-D numerical simulation of flow in natural meandering channel

为了研究天然河道中水流运动规律和河床演变及泥沙冲淤,建立了适体坐标下修正的紊流水流数学模型.采用有限体积法离散控制方程,并运用SIMPLEC算法计算了黄河沙坡头河段连续弯道的三维水流流场,通过实测资料对计算结果进行了对比分析.结果表明,模型计算值与实测值吻合较好,反映了天然连续弯道水流的基本特性,即水面的水质点向凹岸运动,而近底的水质点向凸岸运动.说明该模型可以用于模拟天然连续弯道的水流运动.

In order to study the flow movement, bed evolution and sediment erosion and deposition of the natural rivers, a 3-D numerical model is established in body-riding coordinates by a finite volume method, and SIMPLEC algorithm is used to calculate the 3-D velocity fields. The simulated results of the model are compared with the measured data. The findings indicate that the calculated results agree well with the measured data and reflect the 3- D flow characteristics in the natural meadering channels. The surface water particles will move towards the concave bank, while the bottom water particles will be towards the convex bank. It is shown that the model can be used to simulate the flow movement along the natural meadering channels.