Please use this identifier to cite or link to this item: `http://hdl.handle.net/11455/2550`
 標題: 無介面層之螺栓接合界面模擬之方法No Gap Element Modeling of Bolted Joints Interface 作者: 沈保衡Sen, Pao-Heng 關鍵字: 螺栓接合;介面模擬 出版社: 機械工程學系 摘要: 介面層勁度之模擬在以往都是以彈簧元素來進行模擬，此種方式雖然可以達到模擬界面之目的，但在建構有限元素模型上卻要花費很多的時間。 本文的目的是要簡化螺栓接合介面的模擬，以減少在建構有限元素模型上的時間。文中分別建立無介面層的有限元素模型及有介面層元素之有限元素模型，並比較兩種模型分析結果和實驗量測值的差異。無介面層的模擬方式是使用相鄰介面之兩層有限元素的楊氏係數、剪力模數和結構阻尼係數為變數，藉由調整楊氏係數及剪力模數，配合模態實驗量測到的自然振動頻率和模態，再使用全域搜尋法去修正有限元素模型，最佳化的目標為減少實驗頻率和解析頻率的差，以模態確認標準為限制條件，使修正後的有限元素模型與模態實驗的結果相似，在完成介面勁度的驗證後，再進行阻尼的驗證，亦使用最佳化方法去減少分析和量測的阻尼比的誤差。本文以三種不同形式的螺栓和鎖緊扭力來驗證本文方法的可行度。The correct modeling of interfaces affects the results of finite element analysis. The stiffness of interface was usually modeled by spring elements. Although this approach achieves the purpose of modeling interfaces, the time spent on creating the finite elements model is significant. The purpose of this thesis is to simplify the interface modeling of bolted joints and to reduce the modeling time. Two different models are created in this thesis. One has interface elements and the other one has no interface element. The differences of analyses by these two models are compared. The model without interface elements uses Young's moduli and the moduli and structural damping coefficients of elements neighboring the interface as design variables. The correlation of the finite element model and modal test data are accomplished through optimization procedure. The objective is to minimize the differences of analytical and measured natural frequencies. The MACs are used as constraints. After finishing the identification of stiffness, the optimization procedure is used again to minimize the differences of analytical and measured modal damping ratios. Three different types of bolted joints and three different tightening torques are used to test the proposed method of this thesis. URI: http://hdl.handle.net/11455/2550 Appears in Collections: 機械工程學系所

TAIR Related Article