Abstract：In order to improve the critical speed of multistage centrifugal pump rotor system effectively, the effects of several impact factors on the speed or natural frequency of the rotor are analyzed and compared by means of rotor dynamics and finite element method. Additionally, the vibration modal analysis is conducted based on a whole rotor system, and the corresponding bending and torsional vibration modal shapes are provided as well. A quantitative comparison of the fluid-structure interaction and spin softening effect on natural frequency or critical speed is made, the factors affecting the critical speed of rotor and the optimization methods for the speed are given, and the numerical analysis and experimental results are compared. It is shown that accurately simplifying support, reasonably determining support stiffness and damping matrix are necessary prerequisites for precise predictions of critical speed. The fluid-structure coupling effect is equivalent to add a virtual mass on the rotor. The spin softening effect works by the Coriolis effect. The "dry" and "wet" critical speeds of multistage centrifugal pump rotor are quite different. The calculated and measured critical speeds are in good agreement. The numerical simulation of ANSYS is in a good accuracy and can provide a certain reference for the rotor design of multistage centrifugal pump.
王其磊. 多级离心泵转子固有频率影响因素的比较[J]. 排灌机械工程学报, 2015, 33(1): 31-36.
Wang Qilei. Comparison of influence factors on natural frequency of rotor in multistage centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(1): 31-36.
[1]裴吉,袁寿其,袁建平. 流固耦合作用对离心泵内部流场影响的数值计算[J].农业机械学报, 2009, 40(12):107-112. Pei Ji, Yuan Shouqi, Yuan Jianping. Numerical calculation for effect of fluid-structure interaction on flow field in centrifugal pump[J]. Transactions of the Chinese Society for Agricultural Machinery, 2009, 40(12):107-112.(in Chinese)[2]Yuan Shouqi, Zhang Jinfeng, Yuan Jianping, et al. Effects of splitter blades on the law of inner flow within centrifugal pump impeller[J]. Chinese Journal of Mechanical Engineering, 2007, 20(5): 59-63.[3]刘厚林,徐欢,吴贤芳,等. 流固耦合作用对离心泵内外特性的影响[J].农业工程学报,2012, 28(13):82-87. Liu Houlin, Xu Huan, Wu Xianfang, et al. Effect of fluid-structure interaction on internal and external characteristics of centrifugal pump[J]. Transactions of the CSAE,2012, 28(13):82-87.(in Chinese)[4]袁振伟,王三保,岳希明, 等. 转子径向碰摩非线性流固耦合动力学特性全自由度的动态分析[J]. 机械工程学报, 2008, 44(6):199-205. Yuan Zhenwei, Wang Sanbao, Yue Ximing, et al. Dynamic analysis in full degrees of freedom of rotor′s radial rub-impact with the consideration of nonlinear fluid-structure interaction forces[J].Chinese Journal of Mechanical Engineering, 2008, 44(6):199-205.(in Chinese)[5]Majidi K. Numerical study of unsteady flow in a centrifu-gal pump[J]. Journal of Turbomachinery,2005, 127: 363-371.[6]Goto A, Motohiko N, Yoshyasu S. Hydrodynamic design system for pumps based on 3D CAD, CFD, and inverse design method[J]. Journal of Fluids Engineering, 2002, 124(2): 329-335.[7]蔡君,王宏光.转子临界转速实验与计算的对比分析[J].上海理工大学学报, 2007, 29(5):471-475. Cai Jun, Wang Hongguang. Test and calculation of critical speeds of a rotor[J]. Journal University of Shanghai for Science and Technology, 2007, 29(5):471-475.(in Chinese)[8]朱向哲,袁惠群,贺威. 稳态热度场对转子系统临界转速的影响[J].振动与冲击, 2007, 26(12):113-116. Zhu Xiangzhe, Yuan Huiqun, He Wei. Effect of steady thermal field on critical speeds of a rotor system[J].Journal of Vibration and Shock, 2007, 26(12):113-116.(in Chinese)[9]王东华,刘占生,窦唯.一种改进的转子系统临界转速调整方法[J].航空动力学报, 2008, 23(8):1449-1454. Wang Donghua, Liu Zhansheng, Dou Wei. Improved method for adjusting critical speeds of rotor systems[J]. Journal of Aerospace Power, 2008, 23(8):1449-1454.(in Chinese)[10]施卫东,徐燕,张启华,等. 多级潜水泵内部压力脉动特性[J].排灌机械工程学报, 2014, 32(3):196-201. Shi Weidong,Xu Yan,Zhang Qihua, et al. Characteristics of pressure pulsation in multi-stage submersible pump[J].Journal of Drainage and Irrigation Machinery Engineering, 2014, 32(3): 196-201.(in Chinese)[11]田亚斌. 高速多级离心泵转子动力特性研究[D].兰州: 兰州理工大学能源与动力工程学院,2012.[12]成晓伟. 离心泵转子部件临界转速的分析与计算[D]. 兰州:兰州理工大学能源与动力工程学院, 2009.
