摘要
为深入分析轴伸贯流泵装置断电飞逸过渡过程中水力瞬变特性,通过建立贯流泵全过流系统三维模型,考虑压力沿水深变化进出口边界和重力项影响,对机组全流道进行三维数值模拟,分析不同时刻流量、转速及不同测点静压值变化规律,并与真机试验进行对比。计算结果表明:机组平稳运行4 s后开始断电飞逸,共用时36.98 s达到最大飞逸转速,最大飞逸转速为30.97 rad/s,与试验测量值吻合。断电飞逸过程中,转速下降滞后于流量下降。所得各截面上同一半径不同深度测点静压随时间变化都出现向上增长、波动再下降至平稳的过程。机组飞逸后,尾水流道存在明显偏心区。
In order to analyze the hydraulic transient characteristics of the shaft extension tubular pump device during the poweroff and runaway transition process,a three-dimensional model of the total flow system of the tubular pump was established,and the influence of the inlet and outlet boundary and the gravity term of the pressure along the water depth were considered,thereby the three-dimensional numerical simulation was carried out for the whole flow channel of the unit,the change law of flow,speed and static pressure at different measuring points at different times were analyzed,and compared with real machine test.The calculation results show that the unit starts to run away after 4s of stable operation,and reaches the maximum runaway speed at the time of 36.98 s,and the maximum runaway rotational speed is 30.97 rad/s,which is consistent with the test measured value.During the power-off and runaway process,the speed drop lags behind the flow drop.The static pressure at the same radius and different depth measuring points on each section presents a process of increasing upward,fluctuating and then decreasing to a steady state with time.After the unit runaway,there is an obvious eccentric zone in the tail water flow channel.
作者
何中伟
鲍华
高成昊
舒崚峰
HE Zhongwei;BAO Hua;GAO Chenghao;SHU Linfeng(HuaDong Engineering Corporation Ltd.,Hangzhou 311122,China;Zhejiang Huadong Engineering Construction Management Co.,Ltd.,Hangzhou 311122,China)
出处
《流体机械》
CSCD
北大核心
2021年第7期57-64,共8页
Fluid Machinery
基金
中国博士后科学基金项目(2020M681799)。
关键词
轴伸贯流泵
全过流系统
过渡过程
飞逸
tubular shaft-extension pump
full flow system
transition process
runaway
