|
|
Flow analysis based on wavelet packet decomposition for centrifugal pumps at shut- off condition |
Liu Zhuqing,Bi Huili,Wang Fujun |
(College of Water Conservancy and Civil Engineering,China Agricultural University,Beijing 100083,China) |
|
|
Abstract Based on water hammer theory and the Characteristic Method,a long-pipeline pumping station system with the pipe diameter of 2.2 m was studied under the pump shutdown operation condition.The numerical results indicated that negative pressures were existed along the pipeline under the condition,and the maximum negative pressure is-5.9 m.According to the regular arrangement principles of air valves,18 air valves were installed along the pipeline to control the negative pressure.Three different flow coefficients which are 0.95 and 0.65,0.75 and 0.45,0.62 and 0.62,and three different orifice sizes which are 0.018,0.071,0.196 m2 of air valve were analyzed and compared respectively.The maximum negative pressure are-0.69,-0.70,0.71 m under three different flow coefficient,and-0.88,-0.69,-0.67 m under three different orifice sizes.It is found that the parameters combination in which air valve size is 0.196 m2,inflow coefficient is 0.95,and outflow coefficient is 0.65,is suitable for the pumping station with pipe diameter of 2.2 m
|
Received: 24 March 2011
Published: 30 July 2011
|
|
|
|
[1]Wylie E B, Streeter V L, Suo Lisheng. Fluid Transients in. Systems [ M ]. Englewood Cliffs, NJ : Prentice Hall, 1993.[2]胡建永,方杰,张健 等.空气阀在长距离输水系统中的水锤防止作用[J].人民长江,2008,39(1):63-65.[3]杨开林,石维新.南水北调北京段输水系统水力瞬变的控制[J].水利学报,2005,36(10):1176-1182.[4]郑源,屈波,张健,刘德有,索丽生.有压输水管道系统含气水锤防护研究[J].水动力学研究与进展:A辑,2005,20(4):436-441.[5]杨晓东,朱满林.装有进排气阀的长距离压力输水系统水锤计算研究[J].水利学报,1998,(增刊):60-63.[6]LeeT S,Leow L C. Numerical study on the effects of air valve characteristics on pressure surges during pump trip in pumping systems with air entrainment [ J ]. Interna- tional Journal fi~r Numerical Methods in Fluids, 1999,29 (6) : 645 - 655.[7]AWWA. Manual of Water Supply Practices--MS1 : AirRelease ,Air/Vacuum, and Combination Air Valves [ M ]. Denver: AWWA,2001.[8]Wylie E B, Streeter V L, Suo Lisheng. Fluid Transient of System[ M ]. New York: McGraw-Hill International Book Company, 1983.[9]陈乃祥.水利水电工程的水力瞬变仿真与控制[M].北京:中国水利水电出版社,2005.172-179.[10]赖冬根.长距离输水管线空气阀设置的研究[J].科技情报与经济,2008,18(26):189-191.[11]王福军,白绵绵,肖若富.Flowmaster在泵站过渡过程分析中的应用[J].排灌机械工程学报,2010,28(2):144-148. |
|
|
|