复式断面明渠弯道水流三维雷诺应力模型数值模拟

3D numerical simulation of flow fields for compound open bend channel using Reynolds stress model

采用数值模拟方法研究了复式断面和矩形断面60°弯道明渠的流场结构。自由水面的捕捉采用VOF(Volume of Fluid)法,雷诺时均N-S方程采用雷诺应力模型封闭。对两种断面渠型水力特性的模拟结果进行了比较,结果表明:复式断面弯道明渠在弯道横断面上存在着多涡结构;滩地上的流速大于主槽上的流速;凹岸和凸岸上的自由液面水位差要比矩形断面的小;水流在渠底的横向运动强度要比矩形断面的大;弯道内外侧的压力差也与矩形断面有所不同。

The 60 degree compound open-channel flow is simulated based on the Reynolds Stress Model(RSM) and the Finite Volume Method(FVM). The free fluid surface is simulated by the(Volume of Flow) VOF method. Results obtained show that multi-eddy structures exist in the cross section of the bend part. The velocity magnitude increases from the main channel to the beach. The water head between the concave bank and the convex bank of the compound open-channel flow is more obvious than that of the rectangular open channel flow. On the bottom of the channel, the intensity of the transverse circulation of the compound open-channel flow is higher than that of the rectangular open-channel flow.