侧向折流器对侧空腔和底空腔掺气参数的影响  

Effect of lateral deflector on aeration in the bottom and lateral cavities of flows over spillways

作　　者：聂孟喜[1] 吴广镐[1] 

机构地区：[1]清华大学水利水电工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2003年第8期1116-1119,共4页Journal of Tsinghua University(Science and Technology)

摘　　要：为深入研究突扩突跌掺气设施的掺气特性,在三峡工程深孔水工模型上对时均压强分布、掺气量、掺气浓度等进行了观测与分析。试验结果表明在侧墙形成4个区域,即:侧空腔区、压强骤变区、低压区和稳定区,侧空腔长度和侧墙时均压强均与折流器高度有关。在侧墙低压区有负压存在,其发生位置一般距孔口出口(等高程)约15m左右。在侧墙有少量掺气,掺气浓度在1.3%左右,掺气的主要原因是侧墙冲击点处产生的立轴漩滚对空气的卷吸作用。侧向折流器对掺气量有明显影响。侧、底空腔贯通时,侧空腔是一个重要的通气通道,是保证底空腔充分掺气的重要条件。此研究成果和结论可供突扩突跌掺气坎的设计和科研参考。A model of the ThreeGorges Dam was used to experimentally investigate the characteristics of an aerator with a large vertical drop and a sudden lateral enlargement. The experimental results indicated that the flow regime along the sidewall created by the lateral enlargement could be divided into approximately four zones, i.e., the cavity zone, the pressure transient zone, the lowpressure zone and the constant pressure zone. The lateral cavity length and the pressure on the sidewall were affected by the lateral deflector height. A negative pressure zone formed on the sidewall about 15 meters from the outlet. The aeration density at the sidewall was about 1.3%. The vertical vortex formed by the impact of the diffused flow on the sidewall absorbed air resulting in air entrainment into the sidewall water flow. The air entrainment quantity was affected by the lateral deflector. The lateral cavity on the sidewall is an important aeration mechanism when the lateral cavity is connected to the bottom cavity. 

关 键 词：侧向折流器 侧空腔 底空腔 掺气参数 水工实验 水工模型 压强分布 掺气量 掺气浓度 

分 类 号：TV131.61[水利工程—水力学及河流动力学]