水电站调压阀水力学计算研究

Study on hydraulic calculation of pressure regulating valve in hydropower station

本文以水电站调压阀水力学计算研究为重要课题,采用特征线法建立了引水系统的数学模型,进行调压阀的电站水力学计算。结果表明:调压阀直径为800mm时,水轮机组导叶关闭时间采用导叶直线关机时间7s,同时使调压阀以7s一段直线规律开启,达到全开并滞后10s,调压阀最后50s以一段直线规律关闭,机组转速、蜗壳压力和尾水管压力在安全可靠、经济合理范围内,调压阀减小水锤升压的作用明显,因此以调压阀替代调压井是可行的。

The hydraulic calculation study of the pressure regulating valve of the hydropower station is adopted as an important subject in the paper.The mathematical model of the water diversion system is established by using the characteristic line method.The hydraulic calculation of the water pressure regulating valve is carried out.The results show that the diameter of the water pressure regulating valve is 800mm,the closing time of the guide vane of the hydraulic turbine unit is 7 seconds.Meanwhile,the pressure regulating valve is opened with a straight line rule of 7s,and it is fully opened with a delay of 10s,it is regularly closed at the last 50s straight line of the pressure regulating valve.The unit rotation speed,volute pressure and draft tube pressure are within the safe,reliable,economic and reasonable range.The pressure regulating valve has obvious effect on reducing water hammer pressure rise.Therefore,it is feasible to replace the surge shaft with the pressure regulating valve.