排灌机械工程学报Issue(11)：953-959,7.DOI:10.3969/j.issn.1674-8530.15.0119
立式混流泵站停泵两阶段关阀过渡过程分析
Analysis of transient flow in vertical mixed-flow pumping system during pump stopping period by closing valve in two-phase mode
摘要
Abstract
Based on the features of hydraulic structure in large mixed-flow pumping stations,a mathe-matical model of pump transient stopping process is established by means of characteristics method with combination of pump and valve hydraulic characteristic curves.It is shown that when the pump station encounters an emergency shutdown,the highest pump inverse rotational speed can be as fast as 1.56 times than the rate speed,causing the design limit specified in related design guidelines of pumping station exceeded.This prediction is basically in agreement with the runaway characteristics measured on a prototype of the pump.As a case study,an optimization model is established for a valve on the discharge pipeline in the pump station to be closed in two-phase mode.In the model,the water hammer pressure is used as the objective function,the valve closing angle and time are used as optimi-zing variables with certain constrains.At first,the minimum range of the objective function is deter-mined,and the search step is shortened gradually until the optimized one is achieved.The results show that when the butterfly valve is closed for 88°in first 3 s and then for 2°in the other 20 s,the maximum water hammer pressure is 31.4 m and the maximum reverse flow rate through the pump is 1.0 m3 /s.关键词
混流泵站/水锤压力/特征线法/飞逸特性Key words
mixed flow pumping station/water hammer pressure/characteristic line method/runaway characteristic分类
建筑与水利引用本文复制引用
薛宏林,张驰,李彦军,谢山峰..立式混流泵站停泵两阶段关阀过渡过程分析[J].排灌机械工程学报,2015,(11):953-959,7.基金项目
国家自然科学基金资助项目（51109096）；江苏高校优势学科建设工程项目 （）
