冲击式水轮机折向器方程的探讨

针对单喷嘴冲击式水轮机,在已成熟的混流式水轮机水电站过渡过程计算理论的基础上,引入折向器的调节因素,提出了两种大波动过渡过程求解的方法,即依据出力求解和依据转矩求解.依据转矩求解时只要厂家提供详细的机组特性曲线(即折向器开度、针阀开度与转矩间的关系曲线)即可得出准确的结果,而依据出力求解则需要引进折向器方程,即射到水斗上的流量与折向器开度间的关系函数.因此又从折向器动作的物理本质和冲击式机组特性曲线入手推导出折向器方程,并以一工程实例为依托,对两种方法进行计算对比分析,验证了折向器方程及两种大波动计算方法的合理可靠性.

Discussion on refractor equation of impulse turbine

In the light of impulse turbine with single nozzle, and based on ripe computation theory for transition process of mixed-flow wheel hydropower station, the regulation factors of refractor are introduced, and 2 solution methods for large fluctuation and transition process are put forward, i.e., the solutions based on output and rotation moment. For the solution based on rotation moment, the accurate result can be obtained only according to concrete characteristic curve of turbine (opening degree of refractor, pin valve opening degree and relation curve of torque moment); for the solution based on output, the refractor equation should be introduced, i.e., the relation function of discharge jetting on bucket and opening degree of refractor. The refractor equation is deduced form physical characteristics curve of impulse turbine. Taking a practical example, 2 computation methods are compared and analyzed, and reasonability and reliability of refractor equation and 2 computation methods for large fluctuation are inspected.