Please use this identifier to cite or link to this item: `http://hdl.handle.net/11455/1890`
 標題: 複合材料軸-圓盤系統振動特性之探討Studies of the Free Vibration of Shaft-Disk Systems Made of Composite Materials 作者: 蔡家偉Tsai, Chia-Wei 關鍵字: composite materials;複合材料;couple vibration;shaft;disk;耦合振動;軸;圓盤 出版社: 機械工程學系 摘要: 本文主要目的為建立一含撓性圓盤之複合材料軸系統的有限元素模式。系統包含一撓性旋轉軸與固定於其上的撓性圓盤，並由彈簧與阻尼模擬的軸承所支撐。在固定於旋轉軸上之動座標描述下，以旋轉軸的位移場假設求出其動能，並以此為基礎，推導含撓性圓盤之複合材料軸系統中圓盤的位移場、動能與耦合的動能項。考慮含撓性圓盤之複合材料軸系統的動能、應變能與軸承支撐力所做的功等，採用漢米爾頓原理(Hamilton’s principle)配合有限元素法，推導出定轉速下含撓性圓盤之複合材料軸系統的動態運動方程式。 利用上述有限元素模式，先分析靜止且無支撐之含撓性圓盤之等向性材料軸系統之自然振動頻率與模態，結果與用Visual-Nastran套裝軟體頗為接近，此可驗證本文所推導之模式有一定的正確性。再針對等向性材料與數種不同的複材疊層並考慮含剛性圓盤之複材軸系統、內緣固定外緣無支撐之撓性圓盤系統與含撓性圓盤之複材軸系統等狀況對其振動頻率、模態等動態特性進行探討。最後繪製前述系統之肯博尼圖(Campbell diagram)，從中分析其振動頻率與模態在不同轉速的變化。The objective of this thesis is to develop a finite element model for studying of the free vibration of shaft-disk systems made of composite materials. The system consists of a composite shaft to which the flexible disks are attached. The shaft is supported by bearings which are simulated by springs and dampers. Based on the displacement fields of the rotating shaft and disks referring to the coordinate systems that are fixed on the shaft, the kinetic energy and strain energy of the system are derived. The work done by support forces of the bearings are also considered. By employing the Hamilton's principle together with the finite element method, the equations of motion of the composite shaft system containing flexible disks spinning at constant speed are derived.Analyses of natural frequencies and mode shapes of a free and nonrotating shaft-disk system are carried out. The results are shown to be close to those obtaining using Visual-Nastan software. Furthermore, three types of systems, the flexible shafts with rigid disks, the flexible disks rigidly clamped at its inner edge, and the flexible shafts with flexible disks are analyzed in order to study the influence of the flexibility of the disk on the shaft-disk systems. By using the Campbell diagrams, the frequencies of above systems at different spinning speed are analyzed. URI: http://hdl.handle.net/11455/1890 Appears in Collections: 機械工程學系所