﻿ 基于静强度与疲劳寿命分析的结构孔间距设计

# 基于静强度与疲劳寿命分析的结构孔间距设计Spacing Design of Structure Hole Based on Static Strength and Fatigue Life Analysis

Abstract: In the field of aeronautical engineering, the fatigue damage design of aircraft structures is a difficult but critical point through the damage tolerance design of large civil aircraft. The interaction by the cracks between adjacent hole edges leads to a significant reduction in fatigue life, which is a typical issue of design. As an essential element in aircraft structure, holes are widely used in aircraft design. Compared with the single hole-edge crack problem, the fatigue crack propagation between holes is more complicated due to the above mutual interference. In this paper, the two-hole structure was taken as an example, and the finite element model was adopted to analyze the inter-hole stress and crack propagation, based on damage mechanics. Consequently, the optimal spacing criteria for design were established in the case of lower stress concentration effects and longer fatigue life.

1. 引言

2. 计算模型

2.1. 双孔(多孔)分析模型

Figure 1. Model of porous wall structure

Figure 2. Diagram of the two-hole spacing parameter

2.2. 有限元模型应力分布

2.3. 损伤分析的有限元开发

Figure 3. Stress cloud diagram under far field tensile stress

3. 基于静力分析的双孔间距设计

Figure 4. Curve of maximum stress at different apertures spacing

Figure 5. Graph of relationship between the maximum stress level and the actual size (fixed hole ratio)

4. 结合疲劳寿命的双孔结构分析

4.1. 双孔间距对裂纹萌生寿命的影响

Figure 6. Structural fatigue life affected by the spacing factor

4.2. 双孔间距对裂纹后继扩展寿命的影响

Figure 7. Curve of crack propagation life with spacing

5. 结论

[1] 徐武. 飞机结构多位置损伤分析的权函数法与剩余强度预测[D]: [博士学位论文]. 上海: 上海交通大学, 2012.

[2] Pitt, S. and Jones, R. (1997) Multiple-Site and Widespread Fatigue Damage in Aging Aircraft. Engineering Failure Analysis, 4, 237-257.
https://doi.org/10.1016/S1350-6307(97)00020-4

[3] Conners, E.E., Rosenker, M.V., Carmody, C.J., et al. (2000) National Transportation Safety Board. Railroad Grade Crossings, 22, 656-659.

[4] 李政鸿, 徐武, 张晓晶, 等. 多孔多裂纹平板的疲劳裂纹扩展试验与分析方法[J]. 航空学报, 2018, 39(7): 221867-221867.

[5] 郭树祥, 许希武. 任意多孔多裂纹有限大板的应力强度因子分析[J]. 固体力学学报, 2005, 26(3): 351-358.

[6] 赵晋芳, 谢里阳, 刘建中, 等. 有限板共线多孔MSD疲劳裂纹扩展有限元模拟[J]. 工程设计学报, 2009, 16(4): 256-260.

[7] 刘鸣放, 刘胜新, 陈永, 等. 金属材料力学性能手册[M]. 北京: 机械工业出版社, 2011.

Top