摘要
基于RNGκ-ε双方程紊流模型并结合VOF两相流模型,通过模型试验和数值模拟分析了双涡室旋流竖井流态、流速、压力、消能、空化和泥沙输移特性。结果表明,模拟结果与试验值吻合程度较好,涡室段通过掺气坎补气,掺气更加充分,降低了发生空蚀破坏可能性;实测消能率达到75%以上,消能效果较好;不同粒径泥沙在不同流量下在竖井底部存在泥沙淤积,使得消力井深度减小,小流量运行时淤沙最高可达到消力井深度的72%,但经过一次大洪水后泥沙被清空,淤沙高度降低为井深的1.6%,使旋流竖井保持有足够的消能水垫,不会影响其正常运行。在实际工程中,控制拦污栅大小,避免大颗粒泥沙进入泄洪洞导致拥堵,实践中可通过改变运行方式来控制消力井淤沙高度,使其有足够富裕的水垫深度来满足旋流竖井设计和正常运行要求。
Based on the RNG Κ-ε double-equation turbulence model and the VOF two-phase flow model, the flow regime, flow velocity, pressure, energy dissipation, cavitation and sediment transport characteristics of the double volute chamber vortex shaft were studied using model test and numerical simulation. The results were in good agreement with the experimental values. The vortex chamber was more thoroughly dosed with gas through an aerator device, which reduced the possibility of cavitation erosion. The measured energy dissipation rate exceeded 75%, indicating a good energy dissipation effect. The sediment siltation existed at the bottom of the shaft for various particle sizes at various flow rates, reducing the depth of the stilling well. At low flow operation, the siltation might reached up to 72% of the stilling well’s depth. However, the sediment was cleared away after a big flood and the silt height was lowered to 1.6% of the well depth, enabling the cyclone shaft to have a sufficient water cushion for energy dissipation that would not interfere with its regular functioning. Control the size of the barrage in actual projects to prevent congestion caused by large particles of sediment entering the floodway. In actuality, the operating mode can be altered to control the stilling well’s silting height, ensuring that it has sufficient rich water cushion depth to match the cyclone shaft’s design and regular operation requirements.
作者
蔡豪锋
张建民
陈学艳
王乃飞
颜晶冉
肖发新
吴云峰
CAI Hao-feng;ZHANG Jian-min;CHENXue-yan;WANG Nai-fei;YAN Jing-ran;XIAO Fa-xin;WU Yun-feng(State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China;Three Gorges Ecological Environment Investment Co.,Ltd.,Yichang 443004,China;Changyang Rixin Ecological Management Co.,Ltd.,Yichang 443500,China;Changyang Tujia Autonomous County WaterResources and Lakes Bureau,Yichang 443500,China)
出处
《水电能源科学》
北大核心
2023年第3期112-116,共5页
Water Resources and Power
基金
国家自然科学基金重点项目(52130904)。
关键词
旋流竖井
泥沙输移特性
数值模拟
模型试验
消能
vortex shaft
sediment transport characteristics
numerical simulation
model test
energy dissipation
