侧式进 出水口顶板扩张角对拦污栅断面流速分布影响规律研究  

Study on the influence of the expansion angle of the side inlet outlet roofon the velocity distribution of the trash rack section

作　　者：高学平[1] 曾庆康 朱洪涛[1] 刘殷竹 GAO Xueping;ZENG Qingkang;ZHU Hongtao;LIU Yinzhu(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学水利工程仿真与安全国家重点实验室,天津300072

出　　处：《水利学报》2024年第3期301-312,共12页Journal of Hydraulic Engineering

基　　金：国家自然科学基金项目(52179077)。

摘　　要：抽水蓄能电站侧式进出水口双向过流,其顶板扩张角的大小将直接影响拦污栅断面流速分布是否均匀,甚至出现反向流速。抽水蓄能电站设计规范将3°~5°作为侧式进出水口顶板扩张角的推荐范围,其依据是矩形渐扩管阻力系数最小的扩张角度,但侧式进出水口体型较之复杂很多,因此有必要进一步探讨。本文以某侧式进出水口体型为研究对象,采用数值模拟方法,研究了11种角度的顶板扩张角对出流工况和进流工况拦污栅断面流速分布的影响。结果表明:在出流工况下,随着顶板扩张角的增大,中孔拦污栅断面的主流位置由居中部逐渐向底部降低,断面流速分布由上下基本对称趋于底部大上部小的上下不对称,当顶板扩张角较大时中孔拦污栅断面上部出现反向流速;随着顶板扩张角的增大,边孔拦污栅断面流速分布由基本均匀逐渐变为底部大上部小的不均匀分布;随着顶板扩张角的增大,中、边孔孔口流速不均匀系数均逐渐增大,但中孔拦污栅断面流速分布受顶板扩张角影响更大。在进流工况下,随着顶板扩张角的增大,中、边孔拦污栅断面流速分布及孔口流速不均匀系数均无明显影响。研究成果可为优化侧式进出水口设计提供指导。The two-way flow of the side inlet outlet of the pumped storage power station,the size of the roof expansion angle will directly affect the uniformity of the flow velocity distribution of the trash rack section,and even the reverse flow velocity.The design code of pumped storage power station takes 3°~5°as the recommended range of expansion angle of side inlet outlet roof,which is based on the expansion angle with the smallest resistance coefficient of rectangular diffuser.However,the shape of side inlet outlet is much more complicated,so it is necessary to further explore.In this paper,a side inlet outlet shape is taken as the research object,and the numerical simulation method is used to study the influence of the roof expansion angle of 11 angles on the flow velocity distribution of the trash rack section under the outflow condition and the inflow condition.The results show that under the outflow condition,with the increase of the expansion angle of the roof,the mainstream position of the middle-hole trash rack section gradually decreases from the middle to the bottom,and the flow velocity distribution of the section tends from basically symmetrical to asymmetrical with larger at bottom and smaller on the top.When the expansion angle of the roof is large,the reverse flow velocity appears in the upper part of the middle-hole trash rack section.With the increase of the expansion angle of the roof,the velocity distribution of the side hole trash rack section gradually changes from the basic uniformity to the uneven distribution of the bottom and the upper part.With the increase of the roof expansion angle,the non-uniformity coefficient of the flow velocity at the orifices of the middle and side holes gradually increases,but the flow velocity distribution of the middle hole trash rack section is more affected by the roof expansion angle.In the inflow condition,with the increase of the roof expansion angle,the velocity distribution of the middle and side hole trash rack section and the non-uniformity coefficient

关 键 词：抽水蓄能电站 侧式进出水口 顶板扩张角 拦污栅断面流速 数值模拟 

分 类 号：TV732.1[水利工程—水利水电工程]