混流式水轮机减压管对密封间隙及其周围流场的影响

The influences of relief pipes of Francis hydraulic turbine on the flow field of the sealing clearance and its environs

混流式水轮机转轮上冠和顶盖间的压力腔中所产生的压力脉动会影响机组运行的稳定性。本文以某电站机组为例,通过含减压管的原型水轮机三维全流道湍流计算,分析了压力腔及转轮密封间隙中的压力脉动的形成过程,以及减压管数目对其影响,并且分析了减压管与转轮密封间隙泄漏量的关系。

The pressure fluctuation arising from the chamber between Francis turbine runner crown and the head cover will affect the operational stability of the units. In this paper, the three-dimensional turbulent flow is simulated through the whole flow passage of a power plant. The process of the pressure fluctuation in the chamber and the sealing clearance and the effect of the number of the relief pipes are discussed. At the same time the relation between the relief pipes and t, he leakage rate of the sealing clearance is also discussed.