Analysis and evaluation of Fatigue for Aero-Vehicle body Structures

Each Aero-Vehicle body structures has a tendency to exhume weariness, when a part is more than once stacked the subsequent impact is known as exhaustion. In this paper we compute life of a segment subjected to total weakness stacking. As a rule, the weight punishment can't go on without serious consequences by utilizing weariness limit as suitable anxiety. Most auxiliary segments and parts are affected by unpredictable fluctuating hassles in which the greatest and least burdens are ceaselessly changing. Therefore, need is to utilize a weakness hypothesis which will dissect the harm as a consequence of shifting sizes of anxiety cycles. The paper portrays examination of exhaustion life of a segment under combined weakness stacking utilizing palmgren digger's principle. Keywords: High cycle stress, low cycle stress, residual crack growth, cumulative fatigue damage, damage tolerance.

航空飞行器机身结构均易产生疲劳问题：当构件反复受载时，由此产生的效应即为疲劳失效。本文针对承受复合疲劳载荷的构件，计算其疲劳寿命。通常而言，若仅以疲劳极限作为适宜的应力判据，难以有效规避疲劳损伤风险。绝大多数辅助构件与零部件均会受到无规则波动的载荷作用，其最大与最小载荷始终处于动态变化之中。因此，亟需采用疲劳损伤理论，以分析由应力循环幅值变化所引发的损伤。本文采用帕尔姆格伦-迈因纳（Palmgren-Miner）累积损伤准则，对复合疲劳载荷作用下构件的疲劳寿命展开研究。
关键词：高周应力、低周应力、残余裂纹扩展、累积疲劳损伤、损伤容限。