本研究以有限元素法(Finite Element Method)軟體ANSYS來分析含軟性支承的轉子系統在動態響應的影響。系統的轉軸模擬為Timoshenko樑；假設轉盤為剛體，考慮其質量偏心及陀螺效應(gyroscopic effect)；軸承以線性彈簧及阻尼器模擬。本文探討不同之自轉加速度與軸承勁度，對系統之動態特性的影響。研究結果顯示，不考慮系統阻尼效應時，位移響應的均方根(Root Mean Square)值隨著系統等加速至5000 rpm的時間愈短會愈大，且系統通過第一臨界轉速所引致之最大振幅比第二臨界轉速所引致之最大振幅小。此外，隨著系統等加速至5000 rpm的時間愈短，含阻尼之系統通過第一臨界轉速所引致之最大振幅比第二臨界轉速所引致之最大振幅大。

In the thesis, dynamic response of rotor systems with soft supports is analyzed by using finite element software ANSYS. The shaft of the system is modeled as Timoshenko beam. Disks are considered to be rigid with their mass eccentricities and gyroscopic effect taken into account. Bearings are considered to be linear and modeled as spring-damper sets. The effects of different rotating accelerations and bearing stiffness on the system response are investigated. Results of this research show that when the system is undamped and with a slower acceleration, the root-mean-square value of displacement response will be larger, and the maximum amplitude which occurs after passing the first critical speed is smaller than that after passing the second critical speed.

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