水电站过渡过程计算中尾水系统糙率的取值研究  

Choosing roughness value of tailrace system in transition process calculation of a hydropower station

作　　者：李文欣 张晓宏[1] 陈建国 LI Wenxin;ZHANG Xiaohong;CHEN Jianguo(Faculty of Water Resources and Hydroelectric Engineering,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学水利水电学院,陕西西安710048

出　　处：《水资源与水工程学报》2020年第3期175-179,共5页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金项目(51279162)。

摘　　要：在水电站水力过渡过程计算中,为了满足调节保证计算的要求,管道各项参数指标的正确选择是至关重要的,合理的参数取值是水电站得以安全正常运行的基本保证。结合某水电站工程实例,采用过渡过程通用软件,通过分别改变调压室前管道的糙率和调压室后管道的糙率,对水电站过渡过程计算中尾水系统糙率的取值进行了深入研究。研究表明:在机组丢弃负荷过程中,在其他条件不变的条件下,尾水系统糙率的变化对尾水调压室最低涌浪水位、蜗壳末段最大压力和尾水管进口最小压力皆有影响,在水电站过渡过程计算中,尾水调压室前、后段糙率均应采用可能的最小值较为合理。这些成果对于同类工程的建设具有一定的参考意义。In the calculation of hydraulic transition process of hydropower stations,for the purposes of regulation and calculation,it is very important to set appropriate values for various pipeline parameters,which is also the primary requirement for safe and regular operation of hydropower stations.In this paper,choosing the right roughness value for the tailrace system in the transition process calculation of a hydropower station is deeply studied by changing the roughness values of the pipelines in front of and behind the surge chamber respectively with the commonly used software designed for the calculation of the transition process.From the calculation results it can be seen that the changes of the roughness values had an impact on the lowest surge level in the tailrace surge chamber,the maximum pressure at the end of the volute and the minimum pressure at the inlet of the draft tube during the discarding load process of the equipment unit when the other conditions remained unchanged.In the calculation of hydropower station transition process,it is suggested that the minimum possible roughness values of the pipelines should be adopted regarding to the perimeter of the surge chamber.These findings can provide some reference for the construction of similar projects.

关 键 词：水电站尾水系统 糙率 水力过渡过程 最低涌浪水位 尾水管进口最小压力 

分 类 号：TV732.4[水利工程—水利水电工程]