本研究利用有限元素法分析含黏彈支承之非線性轉子軸承系統的動態響應。系統由轉軸、轉盤、非線性軸承及黏彈支承所構成；轉軸以含旋轉慣量(rotary inertia)及剪力變形效應的Timoshenko樑來模擬；轉盤假設為含質量偏心及陀螺效應(gyroscopic effect)的剛體；非線性軸承則以線性彈簧、非線性彈簧及阻尼來模擬；黏彈支承由線性彈簧與線性阻尼的組合來模擬。本文探討由不同勁度係數與不同阻尼係數所組合而成之黏彈支承對系統之共振頻率及穩態響應的影響。由數值結果顯示，當黏彈支承的勁度係數增大時，系統的共振頻率與共振振幅也隨之增大。當黏彈支承的阻尼係數增大時，系統的共振振幅起初會隨之降低；但當黏彈支承的阻尼係數增大至使系統之共振振幅為最小後，系統的共振振幅將隨著黏彈支承的阻尼係數增大而增大。

Dynamic response of a nonlinear rotor-bearing system with viscoelastic supports is analyzed by using the finite element method in this thesis. Rotating shaft of the system is modeled as Timoshenko beam, which includes the effects of rotary inertia and shear deformation. Disks are considered to be rigid with their mass eccentricities and gyroscopic effect taken into account. Nonlinear bearing is simulated by the characteristics of cubic nonlinear springs, linear springs and linear dampers. Viscoelastic support is simulated by the combination of linear springs and linear dampers. The effects of stiffness coefficient and damping coefficient of viscoelastic support on the resonance frequency and steady-state response of the system are investigated. Numerical results of this research show that, as the stiffness coefficient of viscoelastic support increases, the resonance frequency and the resonance amplitude of the system increase, and as the damping coefficient of viscoelastic support increases, the resonance amplitude of the system first decreases and then increases.

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