• 作者： 侯怡仲; 曾錦煥; 林石甫
• 作者服務機構： 國立交通大學機械工程學系; 新加坡南洋科技大學機械與製造工程學院
• 中文摘要： 在結構動態分析的領域中，有限元素法及模態試驗是最普遍的兩種分析工具。但只依賴有限元素分析之結果而未經相關實驗之驗證即判斷結構的動態特性常導致錯誤結論。本文即在解決有限元素模式的邊界條件模擬誤差，以模態試驗的結果為基準，以最佳化方法找出邊界參數之最佳值。由最佳化的結果可發現，由於找到邊界參數之最佳值，使得懸臂樑的模擬誤差大為降低。
• 英文摘要： Usually, blades in bladed disk assemblies are connected to the disk by a“fir tree,”“pin joint”oreven integral construction; i.e., the blades and disk are machined into one piece In such cases, the rootflexibility cannot be neglected while investigating the dynamic behaviors of the blades. In this paper,by using modal data and optimum techniques, the boundary parameters in the finite element model fora cantilever beam with flexible roots will be identified. The identification problem is transformed intoan optimum problem and then solved based on the Sequential Quadratic Programming (SQP) method. Twoexamples are presented. The first example for a theoretical model is used to verify that the formulationof the optimum problem defined here is workable. In the second example, adequate boundary parametersare identified based on practical modal data. The results show that the first three natural frequenciesobtained from the finite element model are almost the same as the experimental data. The identificationalgorithm developed in this study can be applied to general types of flexible boundaries.
• 中文關鍵字： optimization; boundary parameter; cantilever beam; finite element model
• 英文關鍵字： --