光滑溢流坝过坝水流的二维流场数值模拟及掺气初生点预测

Two-Dimensional Numerical Simulation of the Flow on Smooth Surface of the Overflow Dam and Prediction of the Location of Aeration Inception

通过数值计算对二维光滑溢流坝泄流特性及掺气初生点的位置进行了研究。针对WES剖面溢流坝典型体型,采用RNG k-ε紊流模型,基于VOF方法,求解自由水面下的坝体泄流问题,预测了不同泄流流量下的自由水面线位置,研究了泄流状态下整个流场以及沿坝面水体的流速分布特点。结合边界层发展的数值模拟结果,将边界层厚度与水面线的交点确定为掺气初生点的位置。流场与掺气初生点数值模拟结果与实验值对比表明:计算值与实验值相吻合。

Numerical simulation is conducted to study the discharge characteristics and predict the aerated points of the flow on smooth surface of the overflow dam.The fractional volume of fluid（VOF） model of the water-air two phase flow and RNGk-ε turbulence model are introduced to the 2D model,combined with the calculation model of WES profile spillway to simulate free water surface according to different volumes of flow.It studied the sluicing flow fields and distribution characteristics of dam flow,and defined the location of aeration inception as the intersection point of the boundary layer and the free water surface.