(1.Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. Grundfos Research and Development Center, Suzhou， Jiangsu 215126, China)
Abstract：To solve the vibration issue of one inline circulator pump with specific speed of 221, on the premise of having similar energy characteristics, the blade geometry parameters Z，β2，β1 were optimized to lower the vibration amplitude. In order to investigate the effects of blade geometry parameters on pressure pulsation, radial force and vibration of an inline circulator pump, by applying CFX, the full unsteady flow numerical simulations of inline circulator pumps in different flow conditions were executed both on preoptimized impeller A and postoptimized impeller B. The results indicate that the overall pressure pulsation, radial force and radial force fluctuation amplitude of impeller A are higher than those of impeller B; and blade passing frequency and its harmonics are the domain frequencies for pressure pulsation. Meanwhile, to get a deep understanding on the effect of radial force changing on vibration because of changing the blade geometry parameters, the experimental vibration tests were conducted to measure the vibration velocity of inline circulator pumps with impeller A and impeller B. Result is that vibration amplitudes of impeller A are higher than impeller B under different flow conditions, and blade passing frequency and its harmonics are the domain frequencies for pump vibration. In addition, to further study the effect of the changes of pressure pulsation and radial forces caused by changing blade geometry parameters on vibration, vibration velocities of the inline circulator pump with impeller A and impeller B respectively were measured. The vibration results show that, under different working conditions, the vibration amplitude of impeller A is stronger than impeller B. Blade frequency and its harmonics are the main incentives of the vibration of inline circulator pumps. The comparison between computational and experimental results shows that impeller A has higher vibration amplitude because there are higher pressure pulsation, radial forces and radial force fluctuation amplitude it served. The vibration velocity of postoptimized pump is lower than 1.8 mm/s in the flow range from 04Qd to 1.3Qd, and satisfies the ISO 10816 standard.
［1］Christopher E Brennen. Hydrodynamics of Pump［M］.London:Oxford University Press,1994.［2］Adkins D R,Brennen C E.Analyses of hydrodynamicradial forces on centrifugal pump impellers［J］.Journal Fluids Engineering,1988,110(1):20-28.［3］Barrio R,Fernndez J,Blanco E,et al.Estimation of radial load in centrifugal pumps using computational fluid dynamics ［J］.European Journal of Mechanics B／Fluid,2011,30(3):316-324.［4］谈明高,王勇,刘厚林,等.叶片数对离心泵内流诱导振动噪声的影响［J］.排灌机械工程学报,2012,30(2):131-135.Tan Minggao,Wang Yong,Liu Houlin,et al.Effect of number of blades on flow induced vibration and noise of centrifugal pumps［J］.Journal of Drainage and Irrigation Machinery Engineering,2012,30(2):131-135.(in Chinese)［5］袁寿其,周建佳,袁建平,等.带小叶片螺旋离心泵压力脉动特性分析［J］.农业机械学报,2012,43(3):83-87.Yuan Shouqi,Zhou Jianjia,Yuan Jianping,et al.Characteristic analysis of pressure fluctuation of unsteady flow in screwtype centrifugal pump with small blade［J］.Transactions of the Chinese Society for Agricultural Machinery,2012,43(3):83-87.(in Chinese)［6］González J,Parrondo J,Santolaria C,et al.Steady and unsteady radial forces for a centrifugal pump with impeller to tongue gap variation［J］.Journal of Fluids Engineering,2006,128(3):454-462.［7］邵春雷,顾伯勤,陈晔.离心泵内部非定常压力场的数值研究［J］. 农业工程学报,2009,25(1):75-80.Shao Chunlei,Gu Boqin,Chen Ye.Numerical simulation of unsteady pressure field in centrifugal pumps［J］. Transaction of the CSAE, 2009,25(1):75-80.（in Chinese）［8］Spence R, AmaralTeixeira J.A CFD parametric study of geometrical variations on the pressure pulsations and performance characteristics of a centrifugal pump［J］.Computers ＆ Fluids,2009,38(6):1243-1257.［9］International Organization for Standardization. ISO 10816-1:1995(E) Mechanical VibrationEualuation of Machine Vibration by Measurements on Nonrotating Parts［S］.Geneva:International Organization for Standardization,1995.［10］Willi Bohl. Pumpen and Pumpenanlagen［M］.Grafenau／Wiirtt:LexikaVerlag Press,1979.
