带掺气槽岸边溢洪道挑流消能工水力特性

采用RNGk-ε双方程紊流模型对掺气槽、差动式挑流鼻坎和预挖坑联合运行的岸边溢洪道水流流场进行研究,模拟了具有大曲率水气交界面的挑射水舌和掺气坎水流,分析讨论泄槽流态、掺气槽底板最大冲击压力和差动式挑坎压力分布,给出了挑射水舌以及预挖坑的水流结构与速度分布特性,并将计算值与实验值进行对比,两者吻合良好。研究结果表明:泄槽中4道掺气槽的设置能有效减免发生空蚀破坏,但对泄槽中水面有一定的影响;高扩散低收缩差动式挑流鼻坎与预挖坑的联合运用消能效果理想。

Numerical simulation on hydraulics of lateral spillways with aeration slots and hybrid type flip buckets

The RNG k-ε two-equation turbulent model was employed to study the flow fields of a lateral spillway under combined operation of aeration slots;hybrid type flip buckets and stilling pools.The jets with highly irregular hydropneumatic interfaces and the flows of aeration slots were simulated.The flow patterns in the slot,the largest impact pressure on the slot bottom and the distribution of pressure on the bucket were analyzed.The characteristics of the structure and velocity distribution of the jets and the flows were given.The calculated values were compared with the experimental ones,and they agreed with each other.The results indicate that four aeration slots in the spillway can efficiently avoid the cavitation erosion though they have some influence on their water surfaces.The dissipation effect of the hybrid type flip buckets with the stilling pool is satisfactory.