中闸室弧形闸门关闭过程中泄洪洞水力特性研究

Study on Flow Characteristics of Spillway Tunnel Downstream of Middle-gate Chamber in the Steel Arch-gate Closing Process

基于引入VOF模型的RNGκ-ε模型和动网格模型,模拟了岸边泄洪洞中闸室弧形闸门的关闭过程。并结合物理模型试验,重点研究了中闸室下游泄洪洞内流态、空腔长度、壁面压力等水力特性的变化规律。研究结果表明,中闸室弧形门关闭过程中,随闸门开度逐渐减小,底空腔回流和侧墙水翅等不利流态均会逐渐减弱并消失;空腔长度呈线性规律增加;当闸门开度大于1/2时,在泄洪洞底板和侧壁的冲击范围内,能观测到压力峰值,当闸门开度小于1/2后,压力峰值逐渐减小并消失。此外,数值模拟成果与模型试验成果基本符合良好,验证了数值计算模型的有效性。

Based on RNG k-ε two-equation model, the volume of fraction method for free surface calculation and dynamic mesh mod- el ,the steel arch-gate closing process was simulated successfully at middle-gate chamber with abrupt lateral expansion and bottom offset aerator outlet in spillway tunnel. The variation regular of hydraulic characteristics including flow pattern, cavity length and wall pressure were mainly researched in the Ogee curve section of spillway tunnel assisted by experiment method. The results showed that the worse flow regimes including bottom cavity reflux and lateral wall water wing would gradually weaken and disappear finally. The cavity length increases linearly. If the gate opening is large than 1/2, there are higher pressure peak value and pressure gradient in impacted scope. However, if the gate opening is less than 1/2, the pressure peak would gradually decrease and disappear with the arch-gate closing. Besides, the computational results agreed well with experimental results to verify the validity of numerical method.