複合材料葉片疲勞葉片分析

Abstract

本文提出一套疲勞壽命分析方法，以估算葉片損傷情況，並推估一2.5m玻璃纖維複合材料葉片之疲勞壽命。利用Betz理論和葉片元素法得葉片上風力負載，再經由有限元素法做準靜態分析可以計算葉片上受到的疲勞應力。在疲勞損傷分析中，考慮平均應力及材料老化對疲勞壽命的影響，並使用中央氣象局竹北觀測站的風速資料評估風力葉片的疲勞壽命。

The fatigue life of a 2.5m long glass-fabric composite wind blade is studied using a method constructed on the basis of the modified Goodman diagram and Palmgren-Miner’s cumulative damage rule. The wind load on the wind blade is determined using the Betz theory and blade element method. The fatigue stresses in the wind blade are calculated via a quasi-static approach. The wind speed history collected at Zhubei station of the Central Weather Bureau is used in a numerical example to illustrate the fatigue life estimation of the wind blade using the proposed method.