高速悬臂转子-轴承系统的热致同步振动失稳特性

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中图分类号：TK263.6文献标志码：ADOI：10.7652/xjtuxb202508009 文章编号：0253-987X（2025）08-0088-12

Thermal-Induced Synchronous Vibration Instability Characteristics of High-Speed Cantilever Rotor-Bearing Systems

LIU Yang1'²，YU Chengzhi 1，2 ， YUAN Qi1，2 （1.SchoolofEnergyand Power Enginering，Xi'anJiaotong University，Xi'an7loo49，China；2.Shaanxi Provincial Enginering Laboratoryof Turbomachinery and Power Equipment， Xi'an Jiaotong University， Xi'an 71o049，China）

Abstract： To investigate the influence of journal temperature distribution on thermally-induced synchronous vibration instability （Morton effect） in high-speed overhung rotor-bearing systems， this study establishes a three-dimensional transient thermal bending response model and proposes a novel instability threshold criterion. First，three-dimensional transient thermofluid dynamic calculations are performed for the sliding bearings， considering the cavitation effect and temperature-viscosity effect. A dynamic mesh model is used to simulate the journal whirl under different operating conditions，obtaining the circumferential and axial temperature distributions on the journal surface. Then，three-dimensional solid and one-dimensional beam element finite element models are employed to calculate the thermal deformation and dynamic characteristics of the rotor，respectively. Finally，the established model is validated using experimental test results. The study results indicate that compared to converging whirl and circulating whirl，the diverging whirl generates a greater circumferential temperature difference. At a speed of 10000Δr/min ，the circumferential temperature difference reaches 25K . The closer the circumferential temperature distribution curve of the journal surface is to a sine wave，and the longer the axial length of the high-temperature region on the journal，the greater the thermal imbalance of the rotor. The proposed instability threshold criterion can accurately determine the maximum working speed of the rotor-bearing system，improving it by 7.2% compared to traditional criteria that avoid 10% （204号 of the critical speed. This research provides theoretical guidance for the analytical design of highspeed cantilever rotor-bearing systems.

Keywords： Morton effect; rotor-bearing system; rotor thermal deformation; vibration instability

转子-轴承系统是压缩机、汽轮机、燃气轮机等高速旋转机械的重要组成部分，能够保证转子系统的安全稳定运行。（剩余17829字）