摘要
针对35 MPa超高压多级离心泵转子系统,采用有限元法计算和实验法测试在不考虑密封且刚性支承下的临界转速和静弯曲挠度,得到Madyn2000二维轴对称转子计算模型;通过计算叶轮前后密封口环、螺旋密封轴套在0. 25mm和0. 5 mm两种密封间隙下的压差、刚度、阻尼以及质量动力特性系数,得出了两种密封间隙作用下转子的坎贝尔图和前两阶临界转速;通过计算转子不平衡阻尼位移响应,得出了其共振放大系数为2. 02,小于隔离裕度临界共振放大系数2. 5,额定工作转速下的转子最大位移响应为7. 22μm,小于密封间隙0. 25 mm,满足API工况设计要求。分析表明,离心泵转子系统的密封结构和密封间隙直接影响其临界转速、模态振型以及频率响应。
This work mainly focus on the dynamic characteristic of a real 35 MPa ultra - high pressure muhistage centrifugal pump. By using the finite element method and experimental verification, the critical speed and static deflection of rotor are calculated and verified without considering the seal rigid support. The calculation model is simplified as a 2 - D axis symmetric rotor in Madyn 2000. Then, The pressure difference, stiffness, damping and mass dynamic characteristic coefficients of front sealing ring, back sealing ring and screw seal sleeve are calculated under two conditions of sealing clearance, i. e. , 0.25 mm and 0.5 mm. The first two order critical speeds in hygrometric state and the campbell chart are analyzed under two seal clearance. Finally, the displacement response of rotor with unbalanced damping is obtained. The analysis shows the resonance amplification factor 2.02 is lower than that of 2.5. The maximum displacement response of rotor at rated working speed 7.22 p.m is far less than the sealing clearance 0.25 mm. These results meet the requirements of API design, and indicate that the seal structure and seal clearance in a centrifugal pump have a significant influence on the critical speed, mode shapes as well as frequency response, presenting a reference for real industry application.
作者
雪增红
李方忠
陈燕
张永祥
XUE Zeng-hong;LI Fang-zhong;CHEN Yan;ZHANG Yong-xiang(National Enterprise Technology Center,Chongqing Pump Industry Co.Ltd.,Chongqing 400033,China)
出处
《淮阴工学院学报》
CAS
2018年第5期15-19,共5页
Journal of Huaiyin Institute of Technology
基金
重庆市重点产业共性关键技术创新专项项目(cstc2017zdcy-zdyf0169)
关键词
多级离心泵
密封动力系数
临界转速
频率响应
nmhistage centrifugal pump
sealing dynamic coefficients
critical speed
frequency response
