Determination of damage tolerance and remaining lifefor aeroengine crankcase
-
摘要: 使用有限元的方法,建立了某航空发动机机匣安装座处局部模型,计算得到了不同尺寸裂纹的应力强度因子的形状因子Y.基于BS7910评定方法,利用失效评估图(FAD,Failure Assessment Diagram)确定了机匣安装座结构在工作应力下的可接受裂纹尺寸为84.8 mm,结构的剩余强度随裂纹尺寸的增加而显著降低,焊缝较母材具有更低的损伤容限和剩余强度.使用缩小宽度模拟验证件模拟工作状态载荷进行了验证试验,当裂纹尺寸与试样宽度比值较小时,与模拟验证件的评估结果基本吻合.根据Paris公式,构件在工作应力下的剩余寿命为74 238周次.Abstract: In order to ensure the safety of aircraft, fracture assessment for an aeroengine crankcase was carried out. Based on finite element method, a model for the local crankcase fitting seat was established and the geometry factor Y for different crack lengths was obtained. Using the procedure of BS7910, crankcase damage tolerance was calculated and verified by test, the critical allowable crack length is 84.8 mm and the remaining strength decreases with the increase of crack length. The allowable crack dimension and residual strength of weld are smaller than that of parent metal. The test results are in good agreement with the calculated results when crack is small. The remaining life of crankcase was also calculated using Paris formula.
-
Key words:
- damage tolerance /
- welds /
- fatigue crack propagation
-
[1] 航空工业部科学技术委员会.飞机结构损伤容限设计指南[M].北京:航空工业部科学技术情报研究所,1985 Aviation Industry Science and Technology Commission.Guide to damage tolerance design of aircraft structure[M].Beijing:.Aviation Industry Science and Technology Commission,1985 (in Chinese) [2] GJB776-89,军用飞机损伤容限要求[S] GJB776-89,Military airplane damage tolerance requirements[S] [3] 孙克淋,安伟光,王滨生,等.航天飞机薄壁结构的可靠性分析[J].哈尔滨工程大学学报,2004,25(3):327-331 Sun Kelin,An Weiguang,Wang Binsheng,et al.Reliability analysis of thin-walled structures for shuttle[J].Journal of Harbin Engineering University,2004,25(3):327-331 [4] 李亚智,张向.整体加筋壁板的破损安全特性与断裂分析[J].航空学报,2006,27(5):842-846 Li Yazhi,Zhang Xiang.An analysis of fail-safety and fracture control of integreally stiffened panels[J].Acta Aeronautica et Astronautica Sinica,2006,27(5):842-846 [5] 黄其青,刘进征,殷之平.整体翼梁结构断裂特性分析方法与研究[J].航空计算技术,2006,36(2):114-119 Huang Qiqing,Liu Jinzheng,Yu Zhiping.Fracture characteristics analysis method and study of wing-bean integrated structure[J].Aeronautical Computing Technique,2006,36(2):114-119 [6] Schodel M,Zerbst U,Donne C D.Application of the european flaw assessment procedure SINTAP to thin wall structures subjected to biaxial and mixed mode loadings[J].Engineering Fracture Mechanics,2006,73(5):626-642 [7] BS 7910:2005:Guide to methods for assessing the acceptability of flaws in metallic structures[S] [8] API 579-1/ASME FFS-1:Fitness-for-service[S] [9] R6:Assessment of the integrity of structure containing defect.Revision 4[S] -
点击查看大图
计量
- 文章访问数: 3003
- HTML全文浏览量: 30
- PDF下载量: 1088
- 被引次数: 0
下载:
