摘要
针对飞机典型部位在遭到高速破片攻击后结构整体的战伤状态及破片的剩余行为开展数值模拟。应用LS-DYNA软件,结合有限单元方法(finite element method,FEM)和光滑粒子流体动力学(smoothed particle hydrodynamics,SPH)两者的优势,建立自适应的FEM-SPH耦合模拟方法,并构建2种飞机典型部位的计算模型,采用六面体网格局部细化方法实现了核心位置的精确模拟,并进行试验来验证数值模型;开展了一系列高速冲击战伤模拟,对比了不同工况下破片高速冲击结构后形成的碎片云和破口形貌,并对破片的剩余速度和质量进行分析,确定了破片在结构蒙皮上的临界跳飞角。结果表明:自适应FEM-SPH耦合算法的计算结果与试验结果吻合良好,能够对破片高速冲击战伤进行有效准确模拟;碎片云分布形状随破片速度增加变得狭长,冲击角度会改变碎片云和结构破口形状朝向;碎片云高度和扩散速度随破片速度或角度的变化趋势基本一致并都呈线性关系;破片的速度减少量不随初始速度变化,质量减少量则与冲击速度正相关,两者与冲击角度都负相关;破片临界跳飞角与冲击速度大小基本呈线性关系。
A numerical simulation study is carried out on the overall battle damage circumstances of structures and the residual behavior of fragments after the typical parts of aircraft are attacked by high-velocity fragments.An adaptive FEM-SPH coupling simulation method is established by using the LS-DYNA software and combining the advantages of finite element method(FEM)and smoothed particle hydrodynamics(SPH).Using this coupling simulation method,the computational model of two typical parts of the aircraft is set up,and the accurate simulation of the core position is realized by a local refinement method of hexahedral FEM grids.Experiments were carried out to verify the numerical model.A series of high-velocity impact(HVI)battle damage simulations are carried out.The debris cloud and crater appearance formed after fragment impacting on structure at high velocity under different working conditions are compared,while the residual velocity and mass of the fragment are analyzed.The critical ricochet angles of the fragment on the skin are also determined.The major conclusions are given below.The calculation results of the adaptive FEM-SPH coupling algorithm are in good agreement with the experimental results,and it can simulate fragment HVI damage effectively and precisely.The distribution shape of debris cloud becomes narrow and long with the increase of fragment incident velocity,and the incidence angle can change the shape orientation of debris cloud and crater on the structure.The variation trends of height and spread velocity of debris cloud with incident velocity or angle are basically consistent and linear.The velocity reduction of the fragment does not change with the incident velocity,and the mass reduction is positively correlated with it,both of which are negatively correlated with the incidence angle.The critical ricochet angle of fragment varies almost linearly with the incident velocity.The research results can provide a reference for the damage prediction and rapid maintenance of aircraft after air combat.
作者
叶纪元
杨扬
徐绯
王逸韬
何宇廷
YE Jiyuan;YANG Yang;XU Fei;WANG Yitao;HE Yuting(School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,Shaanxi,China;Aviation Engineering School,Air Force Engineering University,Xi’an 710038,Shaanxi,China)
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2024年第6期132-143,共12页
Explosion and Shock Waves
基金
国家自然科学基金面上项目(12272309)。
作者简介
第一作者:叶纪元(1999-),男,硕士研究生,yejiyuan_@mail.nwpu.edu.cn;通信作者:杨扬(1986-),男,博士,副教授,npuyang@nwpu.edu.cn。
