Theoretical and experimental study on the static stability of labyrinth seals
MA Kai1 ZHANG Wanfu1 ZHANG Yao1 GU Qianlei1 CHEN Luqi1 LI Chun1 YANG Jiangang2
1.Institute of Fluid Machinery and Engineering, School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;
2.National Engineering Research Center of Turbogenerator Vibration, Southeast University, Nanjing 210096, China
Abstract：The static stability of labyrinth seals directly affects the safe and stable operation of a rotor system.This paper proposed an experimental method to identify the fluid-induced force and static stiffness coefficients.A three-dimensional fluid model of the labyrinth seals was established.And the static characteristics under different eccentricities and inlet pressure were studied.Theoretical results show a good agreement with the experiment results.The labyrinth seal with different eccentricities produces a fluid-induced force and a negative direct stiffness, which causes the rotor deviating from the geometric center of the stator.Both the fluid-induced force and negative direct stiffness increase with eccentricity and inlet pressure.The static instability is mainly due to the fact that the fluid velocity in the small clearance increases more rapidly along the seal leakage path.The mass inertial force is increased significantly and the pressure decreases.This results in greater pressure distribution in the larger clearance.The fluid-induced force and negative stiffness that tend to push the rotor away from the stator center are produced, and eventually lead to the static instability of labyrinth seals.
收稿日期: 2018-05-17
出版日期: 2019-10-15
引用本文:
马凯1 张万福1 张尧1 顾乾磊1 陈璐琪1 李春1 杨建刚2. 梳齿密封静态稳定性理论与实验研究[J]. 振动与冲击, 2019, 38(20): 140-147.
MA Kai1 ZHANG Wanfu1 ZHANG Yao1 GU Qianlei1 CHEN Luqi1 LI Chun1 YANG Jiangang2. Theoretical and experimental study on the static stability of labyrinth seals. JOURNAL OF VIBRATION AND SHOCK, 2019, 38(20): 140-147.
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