思林水电站长尾水隧洞取消尾调水力过渡过程分析

思林水电站引水系统为“一洞一管一机＋尾水隧洞”布置型式,压力引水管道长335m,压力尾水隧洞长210m,压力水道水流惯性时间常数Tw=4．13s,尾水反水锤问题十分突出。主要论述了思林水电站取消常规的尾水调压井设计,通过优化流道系统、机组参数、调节系统参数等,有效地解决了长尾水隧洞的反水锤问题,水力过渡过程的稳定性满足规范要求,保证了整个工程安全、经济运行。

Analysis on hydraulic transient of long trailrace tunnel without tailrace surge tank for Silin Hydropower Station

The layout of the water diversion system for Silin Hydropower Station is "single diversion tunnel,single penstock and single trailrace tunnel for single turbine";in which the length of the pressure diversion conduit is 335 m,the pressure tailrace tunnel is 210 m long and the inertial time constant of the flow in the pressure conduit is 4.13 s.Under this condition,the problem of the backwater hammer in the tailrace tunnel is quite serious.So far as this is concerned,the design of the hydropower station with the cancellation of the conventional surge tank for the tailrace is discussed herein,which solves the problem from the backwater hammer for the long tailrace tunnel effectively through optimizing the parameters of the flow conduit system,the turbine and the governing system concerned.With this design,the stability of the hydraulic transient has met the requirement of the relevant specification,and then the safe and economic operation of the project has been guaranteed as well.