基于改进区间法的含多裂纹铝合金蒙皮扩展寿命区间研究  

Study on propagation life interval of aluminum alloy skin with multiple cracks based on improved interval method

作　　者：李耀华 王若丁[2] 耿亚南 LI Yaohua;WANG Ruoding;GENG Yanan(Transportation Science and Engineering Institute,Civil Aviation University of China,Tianjin 300300,China;Aviation Engineering Institute,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学交通科学与工程学院,天津300300 [2]中国民航大学航空工程学院,天津300300

出　　处：《安全与环境学报》2024年第6期2238-2246,共9页Journal of Safety and Environment

基　　金：国家自然科学基金项目(U2033209)。

摘　　要：飞机机身蒙皮的多部位损伤(Multiple-Site Damage, MSD)一直以来都是飞机损伤容限设计与后期维修分析重点考虑的问题之一。为了研究MSD的寿命区间,结合区间理论和区间运算公式、泛灰数理论和泛灰数运算公式及两个运算公式之间的关系,得到可以消除区间运算扩张问题和泛灰数运算失误问题的区间数-泛灰数之间新的转换模型。综合考虑新的转换模型、Paris公式、材料属性、材料尺寸和载荷性质等影响因素,最终得到了2024-T3铝合金板材的MSD裂纹扩展寿命区间:厚度为1.6 mm、不限制长宽时的寿命区间为[90 531, 143 689],厚度1.6 mm、长度240 mm、宽度60 mm时的寿命区间为[11 427, 114 071]。通过验算经典数学算例证明了所研究模型可以消除运算扩张问题和运算失误问题,使运算结果更精确;并进行了三种不同裂纹角度下的MSD裂纹扩展寿命试验,试验结果与理论预测的MSD裂纹扩展寿命区间值相吻合,证明了所研究模型的正确性和有效性。所研究模型可以为MSD裂纹扩展寿命预测和分析提供指导。Multi-site damage of aircraft fuselage skin has always been one of the key issues to be considered in aircraft damage tolerance design and the later stage of aircraft maintenance analysis.To study the life interval of multi-site damage crack,by combining interval theory and interval operation formula,universal grey number theory and universal grey number operation formula,and the relationship between the two operations,a new conversion model between interval number and universal grey number is obtained in this paper to eliminate the problem of interval operation extension and the operation error of universal grey number.By integrating the new conversion model,Paris formula,material properties,material size,load properties,and other influencing factors,the multi-site damage crack propagation life interval of the 2024-T3 aluminum alloy plates is obtained:the multi-site damage crack propagation life interval of 2024-T3 aluminum alloy plate with a thickness of 1.6 mm,unlimited length and width are obtained as[90531,143689],and the multi-site damage crack propagation life interval of 2024-T3 aluminum alloy plate with a thickness of 1.6 mm,effective length of 240 mm,and width of 60 mm is obtained as[11427,114071].In this paper,it is proved that the model can eliminate the problem of operation extension and operation error by checking the classical mathematical calculation,and the result of the operation can be more accurate by using the model.This paper conducts multi-site damage crack propagation life tests under three different crack angles,and the test results of three tests are consistent with the theoretically predicted multi-site damage crack propagation life interval values,which proves the correctness and effectiveness of the research model in this paper.The two validations prove the generality of the improved conversion formula from different angles and specialties.The research model in this paper provides necessary guidance for the prediction and analysis of multi-site damage crack propagation life.

关 键 词：安全工程 多部位损伤(MSD) 区间运算 泛灰数运算 寿命区间 2024-T3铝合金 

分 类 号：X949[环境科学与工程—安全科学]