具局部黏滯阻尼平面構架之振動分析

Vibration analysis of planar frame structures with locally distributed viscous damping

吳家昇(Chia-Sheng Wu)

指導教授 ： 蔡定江

國立臺北科技大學/機電學院/製造科技研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00430

摘要

本文是探討平面構架具局部黏滯阻尼的振動特性。沿用Clough及Penzien對黏滯阻尼的定義，結合具內部黏滯阻尼的軸向運動方程式及Timoshenko樑的運動方程式，利用傳遞矩陣法（Transfer Matrix Method）配合座標轉換矩陣求得具有局部分佈阻尼平面構架系統時之自然頻率及振型。針對阻尼分佈的位置、長度及阻尼值的大小作動態特性分析，由結果顯示各項參數對自然頻率、振型及自由振動響應皆有影響。由本文方法作固定邊界和分支之平面結構等之振動特性的分析可以很方便的歸納出平面構架最佳的阻尼分佈位置，來達到抑制振動的效果。

關鍵字

平面構架 ； 黏滯阻尼 ； 傳遞矩陣法 ； 座標轉換矩陣

並列摘要

This study is to discuss about planar frame structures that have vibration characteristics of internal viscous damping. Based on the definition of Clough and Penzien, this study has combined with the axis motive equation of internal viscous damping and equation of the Timoshenko beam. The natural frequencies and the modes of system are determined by using the Transfer Matrix Method and coordinate changeover Matrix. This study focused on the distributed location, length, and value of internal viscous damping to analyze the moving characteristics. The results show that parameters could affect the value of natural frequencies, vibrated mode, and transient response. The method of this study not only can determine the optimal allocation of distributed damping to dampen the effects of vibration, but also can analyze the characteristics of vibration easily by planar frame structures.

並列關鍵字

Planar frame structures ； internal viscous damping ； Transfer matrix method ； Rotation of coordinate matrix

參考文獻

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