连接引水管道的水轮机暂态过程计算  

Transient simulation of turbine jointed with diversion penstock

作　　者：樊红刚[1] 黄伟德[1] 陈乃祥[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《排灌机械工程学报》2012年第6期695-699,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(50879037);水沙科学与水利水电工程国家重点实验室自主研究课题(2008-ZY-2)

摘　　要：考虑水轮机工况变换过程中引水管道内瞬变流与机组内部暂态流动的相互影响,对管道瞬变流采用特征线法求解,机组内部暂态流动采用三维不可压缩流动的有限体积法求解,按照管道与机组连接处流量连续和水头平衡的原则,建立了管道瞬变流与机组内部三维暂态流动的耦合计算模型.并分别采用建立的耦合计算模型、电站常规过渡过程计算模型和常规三维流动计算模型对带有引水管道的水轮机甩负荷导叶关闭工况进行了仿真计算.结果表明:3种计算方法得到的机组压力、转速等宏观参数变化趋势一致,但采用耦合计算模型时,由于考虑了管道内水击压力的反射和叠加,导叶关闭过程中蜗壳进口的压力上升更高,机组内的压力脉动也更剧烈,能够更真实地反映动态过程中管道瞬变流与机组内部三维暂态流动的相互作用.With consideration of the influence of transient flow in pipe during a transition of operation condition,a coupled calculation model for the transient flow in a pipe and three-dimensional unsteady flow in a turbine was developed in this paper.The transient flow in pipe was calculated by the characteristic method and the unsteady flow in the turbine was calculated by the finite volume method for three-dimension incompressible flows.A coupled iteration was carried on at the interface between the pipe and the turbine based on the continuity of flow and the balance of total pressure of water.Three methods,including coupled calculation method,traditional transient simulation method and traditional three-dimensional flow calculation method,were used to simulate the load-rejection transient process of a hydraulic turbine with diversion penstock.The results showed that the trends of pressure,flow of unit and rotational speed,etc,are consistent in all three methods.However,because the reflection and superposition of water hammer wave is considered in the coupled calculation method,the increase in water hammer pressure at the spiral inlet is higher and the pressure fluctuation in the turbine is stronger,suggesting the method can reflect the interaction between transient flow in the pipe and three-dimension unsteady flow in the turbine more realistically.

关 键 词：水轮机 暂态过程 特征线法 非定常流动 耦合计算 管道 

分 类 号：S277.9[农业科学—农业水土工程] TK72[农业科学—农业工程]