液体密封压力差对转子系统动力学性能的影响  

Influences of Liquid-seal Headdrop on the Dynamic Properties of a Rotor System

作　　者：袁振伟[1] 王三保[1] 岳希明[1] 李志农[1] 褚福磊[2] 

机构地区：[1]郑州大学化工与能源学院,河南郑州450052 [2]清华大学精密仪器与机械学系,北京100084

出　　处：《润滑与密封》2010年第11期4-8,共5页Lubrication Engineering

基　　金：国家自然科学基金资助项目(50775208);河南省基础与前沿技术研究计划项目(092300410037)

摘　　要：利用数值方法,通过求解基于Bulk-flow模型的液体动压环状密封控制方程,得到不同密封压力差下液体动压环状密封的动力特性系数。结合密封的流体动反力模型,建立考虑液体动压环状密封动力学特性的系统运动方程,通过理论分析导出表征系统动力学性能的模态阻尼与频率、振幅对数衰减率以及动力放大系数等的解析表达式,并计算分析密封压力差对转子系统动力学性能的影响。结果表明:正、反向涡动模态阻尼和正、反向涡动的振幅对数衰减率均随密封压力差的增加而增大,动力放大系数随密封压力差的增加而减小,而正、反向涡动模态频率先随密封压力差的增大而减小,达到最小值后又随密封压力差的增加而增大。The dynamic coefficients of a given liquid annular seal under different headdrops were obtained by numerically solving the governing control-volume equations based on bulk-flow model. Equations of motion of the system considering the seal＇ s dynamic properties were established by integrating the fluid dynamic reaction-force model of the liquid annular seal into the dynamic model of the system. The analytical expressions of modal damping and frequency,logarithmic decrement and dynamic magnification factor, which represent the dynamie properties of the system, were obtained by theoretical analyses. The influences of liquid-seal headdrop on the dynamic properties of the rotor system were discussed. The results show that, for both forward and backward whirls of a rotor, with the increase of the headdrop, the modal damping and logarithmic deerement increase, the dynamic magnification factor decreases, and the modal frequency goes down at first, then gets to a minimum value, and goes up afterward.

关 键 词：转子系统 动力学性能 液体动压环状密封 密封压力差 

分 类 号：TH113[机械工程—机械设计及理论]