Vibration Analysis of Pre-Twisted Windmill Blade under Rotating Conditions

風車翼片在旋轉狀態下之振動分析

劉勝安(Sheng-An Liu) ； Chen-Yee Hong

《中華民國振動與噪音工程學會論文集》 2011 (2011/06) Pp. 341-349

https://doi.org/10.30028/CSSVANNUAL.201106.0341

摘要

本研究針對具線性預扭風車翼片在旋轉狀態下之自然振動頻率與對應振型進行深入之分析。首先結合Hamilton動力學原理推得樑元素在旋轉狀態下之有限元素運動方程式，並推出質量矩陣、線剛性矩陣、慣性阻尼矩陣、因座標旋轉產生之剛性矩陣、軸向拉力所產生之幾何剛性矩陣。而根據所推得之矩陣撰寫有限元素求解程式，並求得翼片在不同之旋轉速度、裝置條見與預扭角之組合條件下之自然振動頻率與相對應之振型。

關鍵字

風車翼片 ； 自然振動 ； 有限元素法

並列摘要

The natural vibrating behavior of a linearly pre-twisted windmill blade of composite cross section is investigated using finite element analysis. Application of three dimensional beam theory embedded in the Hamilton's principle of dynamics leads to equations of motion of an element. The consistent mass matrix, linear stiffness matrix, inertial damping matrix, stiffness matrix due to frame rotation, and geometric stiffening stiffness matrix due to tension preload (centrifugal forces) are derived. A structural module for analysis of the fundamental vibration of a beam is then developed to obtain the various vibrating modes of blades under rotating conditions. A number of total pre-twist angles, blade root angles, blade rotating speed, and radii of hub are assumed so that effects of such parameters on the natural frequencies of the rotating blades may be realized.

並列關鍵字

Windmill Blade ； Natural Vibration ； Finite Element Analysis