飞机冲击载荷等效静载的确定方法研究  

A method to determine the equivalent static load of aircraft impact load

作　　者：张玉杰[1,2] 黄超广 李斌 ZHANG Yujie;HUANG Chaoguang;LI Bin(School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China;Department of Strength Engineering Research,AVIC The First Aircraft Institute,Xi’an 710089,China)

机构地区：[1]西北工业大学航空学院,西安710072 [2]航空工业第一飞机设计研究院强度设计研究所,西安710089

出　　处：《航空工程进展》2023年第3期157-163,177,共8页Advances in Aeronautical Science and Engineering

摘　　要：如何确定冲击载荷的等效静载对飞机结构的强度设计和验证具有重要意义。基于经典冲击载荷时域曲线后峰锯齿波、单自由度冲击动响应理论和位移等效原则,建立冲击载荷动态缩放系数求解公式;基于三角函数不等式关系,推导出动态缩放系数与冲击载荷作用时间、结构固有频率乘积的函数关系。建立求解冲击载荷等效静载方法的实施流程;以简化拦阻钩系统的冲击和缩比模型的水上迫降为例,对所提方法的有效性进行验证。结果表明:拦阻冲击载荷动态缩放系数的理论估计值与仿真计算值的相对误差小于4%,水上迫降等效静压与选用的设计压力相对误差为0.9%,所建立的动态缩放系数的理论计算公式精度较高,所提方法可供工程相关应用参考。It is significant to determine the equivalent static load of impact load for the strength design and verifica-tion of aircraft structures.The formula to calculate shock load dynamic effect coefficient is established based on ter-minal peak saw-tooth shock pulse describing the time history of shock load,single freedom dynamic response mod-el and the equivalent principle of model displacement.Then the function relationship between dynamic effect coeffi-cient and the product of shock load duration and model natural frequency is deduced from trigonometric function in-equality.The flow chart to determine equivalent static load of shock load is drawn according to the above theory.Fi-nally this method is used to verify the equivalent static load of arresting hook system and aircraft model ditching pro-cess.The comparative results show that the maximal relative error of dynamic effect coefficient of arresting impact load is below 4%between theoretic estimated values and numerical simulated values by FEM,the relative error of equivalent static pressure during model ditching test is below 0.9%between theoretic estimated value and deter-mined design value.It shows that the theoretical calculation formula of the established dynamic effect coefficient has a high accuracy,and the proposed method has certain engineering application value.

关 键 词：冲击载荷 等效静载 后峰锯齿波 位移等效 动态缩放系数 结构强度设计 

分 类 号：V215.1[航空宇航科学与技术—航空宇航推进理论与工程] V415.4