军用飞机结构耐久性设计的细节疲劳额定值方法

 为满足军用飞机研制初步设计阶段对结构耐久性(疲劳)快速设计与评估的迫切需求,在全面分析军用飞机与民用飞机主要区别的前提下,针对军用飞机结构与使用载荷特点,以民用飞机细节疲劳额定值(DFR)方法的基本思想和技术途径为基础，从寿命服从对数正态分布的假设出发,对随机载荷谱的当量等幅化方法、结构DFR许用值的确定技术以及标准S--N曲线的建立等关键问题进行深入研究,建立了适用于军用飞机的DFR方法及相应的工程实施技术。初步应用表明方法可行且偏保守,能明显缩短研制周期、降低研制成本,具有重要的工程意义和应用价值,可用于军用飞机研制的初步耐久性设计。

Military Aircraft Durability Design Method Based on Detail Fatigue Rating

To meet the rapid design and assessment requirements of structural durability (fatigue) analysis for military aircraft development in the preliminary design stage, characteristic differences between military aircraft and civil aircraft are summarized, and detail fatigue rating (DFR) approach suitable for military aircraft structure and service load is presented. Based on principle and technology of civil aircraft DFR approach, assuming that fatigue life follows logarithm normal distribution, some pivotal problems with military aircraft characteristics are studied, such as determining constant load amplitude equivalent to random load spectrum, structural DFR allowable value, specific S--N curve, engineering implement process of DFR approach, etc. Preliminary application shows that it is feasible and conservative, can significantly shorten development time and reduce cost during the initial durability design of military aircraft. It has important engineering significance and application value.