本文以有限元素法 (Finite Element Method)模擬油膜軸承應用於人字齒輪轉子系統之動態行為。本文系統的轉軸為Timoshenko樑，使用Timoshenko樑需要考慮剪應力及轉動慣性；轉盤假設為剛體，並考慮其陀螺效應及質量偏心；軸承以油膜軸承來模擬，在不同的轉速下會有不同的勁度係數與阻尼係數；齒輪對視為線性彈簧及阻尼器沿著壓力線連接的兩個剛性轉盤來模擬。本文探討不同參數對於油膜軸承應用於人字齒輪轉子系統之差異。本文改變齒輪螺旋角度、齒輪嚙合勁度係數及齒輪置放於不同的節點，並探討對系統自然頻率、側向及軸向響應的影響。從結果得知，改變齒輪上的變數對系統之側向-扭轉耦合模態影響較大。

In this thesis, dynamic behavior of a double-helical geared rotor system with oil-film bearing is studied by using the finite element method. Rotating shafts are modeled as Timoshenko beam, which includes shear deformation and the effect of rotary inertia. Bearings are modeled as oil-film bearings whose stiffness and damping coefficients vary as the rotating speed changes. Disks are assumed to be rigid, and their gyroscopic effect is taken into account. The gear mesh is modeled as a pair of rigid disks connected with spring-damped set along the pressure line. In this thesis, effects of parameters, such as helical angle, gear mesh stiffness, and different location of gears on natural frequency, lateral response, and axial response of the system are studied. Numerical results show that the resonant response in axial direction of the double-helical geared rotor system with oil-film bearing is small. By calculating the response of different nodes, it can be found that the node is closer to the middle of the rotating shaft, the lateral response is greater, otherwise, the node is closer to the bearing position, the lateral response is smaller. As the stiffness of gear mesh increases, the resonance frequencies of the system increase on the lateral-torsional coupling modes of the system.

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