本研究以有限元素法來分析含複合材料轉軸之齒輪轉子軸承系統的動態行為。系統由轉軸、轉盤、線性軸承及齒輪對所構成。轉軸是由複合材料所組成且模擬為Timoshenko樑，即考慮轉軸之旋轉慣性及剪應變效應，轉盤假設為剛體，並考慮質量偏心及陀螺效應，軸承以線性彈簧及線性阻尼器來模擬；齒輪對視為由彈簧及阻尼器沿著壓力線連接的兩個剛性轉盤。本文分別探討轉軸疊層方式、齒輪嚙合勁度係數、軸承勁度係數及軸承阻尼係數，對系統共振頻率與側向穩態響應的影響。由數值結果顯示，隨著齒輪嚙合勁度係數的提升，系統耦合振動的共振頻率會隨之提升，而系統耦合振動的共振響應會隨之下降。當軸承的勁度係數增大時，系統的共振頻率也隨之增大。當軸承的阻尼係數增大時，系統的共振響應起初會隨之降低；但當軸承的阻尼係數增大至使系統之共振響應為最小後，系統的共振響應會著阻尼係數的增大而上升。

Dynamic behavior of a geared rotor-bearing system with composite shafts is analyzed by the finite element method in this thesis. Rotating shafts of the system are composed of composite material and modeled as Timoshenko beams, which includes the effects of rotary inertia and shear deformation. Disk is considered to be rigid with its mass eccentricity and gyroscopic effect taken into account. Bearings are considered to be linear and modeled as spring-damper sets. The gear mesh is modeled as a pair of rigid disks connected by a spring-damper set along the pressure line. Effects of stacking sequence of rotating shaft, mesh stiffness coefficient of gear pair, stiffness coefficient and damping coefficient of bearings on the resonance frequency and steady-state response of the system are investigated. Numerical results of this research show that, as the mesh stiffness coefficient of gear pair increases, the resonance frequencies of the coupled vibration increase and the resonance responses of coupled vibration decrease. As the stiffness coefficient of the bearings increases, the resonance frequencies of the system increase, and as the damping coefficient of bearings increases, the resonance response of the system first decreases and then increases.

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