本研究以有限元素法 (Finite Element Method)模擬人字齒輪於轉子軸承系統之動態行為並以ANSYS軟體來驗證人字齒輪轉子軸承系統。系統轉軸模擬為Timoshenko樑，即考慮轉軸的剪應變效應及旋轉慣性；轉盤假設為剛體，並考慮其陀螺效應及質量偏心；軸承以線性彈簧及阻尼器來模擬；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。本文探討斜齒輪轉子軸承系統與人字齒輪轉子軸承系統於軸向響應之差異。改變齒輪螺旋角度、齒輪嚙合勁度係數、齒輪傳遞誤差及齒輪位於不同節點，對系統自然頻率、側向及軸向響應的影響。從理論及前述模擬得知，人字齒輪相較於斜齒輪產生的軸向響應較小。從數值結果得知，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 analysis of a double-helical geared rotor-bearing system 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 linear spring-damper. Disks are considered 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, we discuss about the difference of axial response between helical geared rotor-bearing system and double-helical geared rotor-bearing system and the effects of parameters, such as helical angle, gear mesh stiffness, transmission error of gears, and different location of gears on natural frequency, lateral response, and axial response of the system. Software ANSYS is used to verify results for double-helical geared rotor-bearing systems. Numerical results show that the resonant response in axial direction of the double-helical geared rotor-bearing system is smaller than that of the helical geared rotor-bearing system, and that parameters of gears have much influence on the lateral-torsional coupling modes of the system.

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