运输类飞机疲劳寿命分析的一种新方法

摘要

为了使DFR法能够适用于一般运输类飞机的疲劳分析，对DFR法进行了改进。从飞机各典型飞行任务剖面的使用比例（飞行次数比例）导出其在整个寿命期内所占的损伤比例，进而获得了当量剖面的损伤；然后再以当量剖面的损伤为基准，计算地-空-地(G-A-G)损伤比，再导出当量地-空-地循环数，最后确定出地-空-地循环许用应力和疲劳裕度。改进后的DFR法已应用于实际的工程设计。%In order to make the DFR method applicable to the fatigue analysis of the transport aircrafts, improvements were made on the typical DFR method. Damage proportions of each typical lfight mission section can be derived through the different mission proifle and the proportions lfight. Furthermore, the damage of the equivalent mission proifle can be obtained. Then, based on the damage of the equivalent proifle, the G-A-G damage proportion and the equivalent G-A-G cycle number can be concluded. Finally, the allowable stress of G-A-G cycle and the fatigue tolerance can be determined. The improved DFR method has been successfully applied in engineering practice.