Effects from O-rings on the Stability of a Rotor-porous Air Journal Bearing Test-rig

doi:10.3901/JME.2025.05.117

Abstract

Abstract: Testing and stability evaluation are conducted on a rotor-porous air journal bearing test-rig with O-rings as the damping structure. The working principle of porous air journal bearings and the system is systematically elaborated. The dynamic stiffness and damping values of O-rings made by different material are tested by the excitation experiment. The data shows that the greater the stiffness of the O-ring, the greater its damping value. The effects of parameters such as rotational speed, gas supply pressure and O-ring material on the system stability are studied by the rotor experiment. The results show that the change of the supply pressure has a low effect on the amplitude of synchronous vibration at the rotor center, but increasing the supply pressure can suppress the subsynchronous vibration generated by the rotor at high speeds. The VMQ (methyl vinyl silicone rubber) system has the best stability, and the rotor can maintain 1 μm synchronous amplitude at high speed 17～27 kr/min. The stability of the SBR (styrene butadiene rubber) system is the worst, because the rotor is prone to produce subsynchronous vibration at low supply pressure, and the amplitude of synchronous vibration is also too large. The stability of the HNBR (hydrogenated nitrile butadiene rubber) system is moderate. The results indicate that there are significant differences for the above three O-rings in influencing the stability of the system.

Key words: O-rings, porous air journal bearings, rotor stability, experimental analysis

CLC Number:

TH133

ZHANG Kang, HU Haidong, GUO Minghui, CUI Hailong, HUANG Yu, RONG Youmin. Effects from O-rings on the Stability of a Rotor-porous Air Journal Bearing Test-rig[J]. Journal of Mechanical Engineering, 2025, 61(5): 117-125.

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