Abstract:Turbine rotor systems usually lose stability caused by Alford forces. Thus, dynamic characteristics and stability analysis of the multi-span rotor system of a practical compressor unit subjected to Alford forces were investigated. The Newmark-β method combined with the fixed interface Component Mode Synthesis (CMS) dimension reduction approach was applied to obtain the dynamic response due to much degrees of freedom of the large scale rotor system, and computational efficiency was improved obviously. The effects of cross stiffness, working speed on rotor whirling and the transmission acting of Alford forces on multi-span rotor system were investigated; taking the time-history curves as stability criterion, stability analysis with different parameters were discussed. It shows that rotor whirling will aggravate and stability decreases with increasing cross stiffness; stability is improved with the increase of damping and stiffness of system; while instability is apt to occur when the cross stiffness induced by Alford force is larger than the minimum cross stiffness of bearings and that is close to the maximum cross stiffness of bearings.
赵 倩,许 琦,姚红良,闻邦椿. 多跨转子系统流体引发自激振动稳定性分析[J]. 振动与冲击, 2016, 35(5): 196-200.
ZHAO Qian,XU Qi,YAO Hong-liang,WEN Bang-chun. Stability analysis of a multi-span rotor system with self-excited vibration initiated by fluids. JOURNAL OF VIBRATION AND SHOCK, 2016, 35(5): 196-200.
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