摘要
单次起落平均飞行距离是民机使用情况的主要表征量。它的随机性使得机队中每架飞机的过载超越频次曲线不同和相同过载下的应力不同,从而导致载荷谱的分散。地空地循环是民机疲劳损伤的主要来源,考虑平均飞行距离随机性,着重分析地空地循环载荷的分散,采用蒙特卡罗法模拟其分布参数,并根据结构的S—N曲线计算地空地损伤的分布。结果表明:(1)使用情况差异导致的地空地损伤的分散可以用对数正态分布描述;(2)该分散性主要受飞行距离标准差的影响,均值的影响很小。
Average GCFL （ great circle flight length） per flight is a main characterization for the operational usage of civil aircraft. The variation of GCFL in a fleet leads to the incremental load exceedance curve and the load-stress transfer factor of every aircraft differs with each other, which cause the scatter of load spectrum. GAG （ground-air-ground） load cycle is the main source of the fatigue damage of civil aircraft. Taking the variation of GCFL into account, a method to predict the scatter of GAG damage is presented. Monte Carlo method was adopted to stimulate the distribution of GAG load cycle, and then the distribution of GAG damage was evaluated. The result shows that the GAG damage scatter caused by the variation of aircraft usage can be approximately described by lognormal distribution, and the scatter is mainly determined by the standard deviation of the average GCFL yet the mean value has little effect.
出处
《机械强度》
CAS
CSCD
北大核心
2013年第5期668-673,共6页
Journal of Mechanical Strength
关键词
载荷谱
疲劳可靠性
使用情况
分散系数
地空地循环
民用飞机
Load spectrum
Fatigue reliability
Operational usage
Scatter factor
Ground-air-ground （GAG）load cycle
Civil aircraft
