本研究以有限元素法分析含複合式轉軸之轉子軸承系統的動態特性。複合式轉軸為一實心金屬軸在內與包覆在外之複合材料組合而成，系統轉軸模擬為Timoshenko Beam。本研究系統之轉盤為剛體，軸承以線性彈簧及阻尼器模擬。本文採用ANSYS軟體進行模型建立與數值模擬分析。本研究將探討應用金屬與複合式轉軸之轉子軸承系統動態特性。 研究結果顯示，隨著複合材料層之纖維與平行轉軸方向夾角減小，系統側向自然頻率會顯著提升，而複合材料層之纖維與平行轉軸方向夾角越接近 度則扭轉自然頻率會大幅提升。

In the thesis, dynamic characteristics of rotor-bearing system with hybrid shaft is analyzed by using finite element software ANSYS. The shaft of the system is modeled as Timoshenko beam. Disks are considered to be rigid and gyroscopic effect taken into account. Bearings are considered to be linear and modeled as spring damper set. The hybrid shaft is combined by metal shaft inside and bounded with composite layer outside. The metal shaft was built by aluminum, the composite layer was built by graphite/epoxy. The contact face between metal shaft and composite layer is considered to be perfectly bonded. The analysis of the vibratory characteristics of a rotor bearing system with hybrid shaft subject to orientation of fibers and the numbers of disks, is presented in the paper. The bending nature frequency and critical speed can be raised up to almost 50% for the rotor bearing system with hybrid shaft. The torsional nature frequency can be raised up to almost 45%. The hybrid shaft can provide enough bending and torsional stiffness with right stack of composite reinforcement.

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