航空发动机转子盘腔积油振动故障分析

结合工程中航空发动机转子在试验中遇到的积油振动问题,从积油振动理论、动力学特性和振动信号分析方面展开研究,剖析了转子盘腔积液故障机理,获得了所引起转子失稳振动的特征及规律,建立了盘腔积油故障识别的流程和准则,以及其振动监控指导。研究表明:积油在转子临界转速以上的特定区域才会产生明显的次谐波振动,引起转子自激振动,自激振动频率与转子1阶临界转速接近;在临界转速以下,仍以转频振动为主,且积油会导致过临界转速峰值增大;上述故障识别的流程和准则应用在某发动机试验件转子,准确地识别出盘腔积油特征,验证本文研究结论的正确性。 

Vibration fault analysis of aeroengine rotor disk cavity filled with oil

In combination with the problems of rotor cavity filled with oil vibration encountered in the test of aero engine rotor in the project, the research was carried out from the theory of vibration, dynamic characteristics and vibration signal analysis, and the failure mechanism of rotor disk cavity filled with oil was analyzed. The characteristics and regularity of instability vibration were acquired, the process and criteria for disc cavity fluid accumulation fault identification as well as its vibration monitoring guidance were established. The result showed that the subharmonic vibration was produced when the rotor speed was above the critical speed of the rotor if the rotor cavity was filled with oil, which caused the self-excited vibration of the rotor; and the frequency of the self-excited vibration was close to the first order critical speed of the rotor; and the rotor frequency vibration was still dominant when the rotor speed was below the critical speed, and the oil deposit could cause the increasing peak value of the over critical speed; the above-mentioned fault identification process and criteria were applied to an rotor of an engine to accurately identify the characteristics of rotor cavity filled with oil. Oil was found in the fan''s secondary disk cavity when the rotor was dismantled. After cleaning up the oil, the abnormal vibration disappeared, which verified the correctness of the conclusions.