飞机典型结构累积毁伤效应及毁伤机理

Research on Cumulative Damage Effects and Damage Criteria of Typical Aircraft Structures

飞机在高速武器攻击下的生存力是至关重要的。这一仿真研究的主要目的就是研究某型飞机在未来空中可能遇到的武器威胁。通过模拟研究典型战斗部爆炸产生的冲击波和破片对飞机典型部位的高速冲击毁伤,得出一些有应用价值的结论。本研究针对冲击波单独加载、先冲击波加载-后破片侵彻、先破片侵彻-后冲击波加载3种混合作用模式,分析不同作用模式对结构整体变形和局部破坏的影响规律,探明破片与冲击波混合作用下的典型结构累积毁伤效应。本研究基于FEM-SPH自适应耦合算法,建立了高拟真度飞机典型结构的数值毁伤模型,并开展试验对模型进行了有效性验证。数值仿真研究中,以某典型战斗部为背景,进行了球形破片杀伤元和不同爆炸比距离冲击波杀伤元下飞机典型结构损伤的对比;讨论了钛合金结构不同的损伤情况;最后分析了飞机结构典型毁伤模式、损伤转化条件以及损伤机理。结果表明:在高速破片和冲击波联合毁伤情况下,飞机结构战斗损伤与交会条件高度相关;在冲击波的预先加载下,金属结构出现大范围塑性变形区,后破片侵彻损伤形式多表现为剪切损伤和撕裂损伤。随着冲击波比距离增加,金属结构出现大范围撕裂分离现象。经过冲击波加载下的金属结构强度明显降低,破片剩余速度和剩余质量明显高于单独侵彻情况。而后加载的冲击波会对侵彻产生的破口毁伤形貌进行二次改变,出现边缘撕裂和裂纹拓展现象。本研究结论可为飞机防护性设计提供参考,为部队抢修演练战伤预置提供基本输入。

aircraft survivability under high-speed weapons attack is critical.The main purpose of this simulation study is to study the weapon threats that a certain type of aircraft may encounter in the air in the future.By simulating and studying the high-speed impact damage to typical parts of the aircraft caused by shock waves and fragments generated by typical warhead explosions,some conclusions with application value were drawn.This study focuses on three mixed action modes of shock wave loading alone,shock wave loading first and then fragment penetration,and fragment penetration first and shock wave loading later.It analyzes the influence of different action modes on the overall deformation and local damage of the structure and explores the relationship between fragments and shock waves.Typical structural cumulative damage effects under mixing.Based on the FEM-SPH adaptive coupling algorithm,this study established a numerical damage model of a typical aircraft structure with high fidelity and conducted experiments to verify the effectiveness of the model.In the numerical simulation study,a typical warhead was used as the background to compare the typical structural damage of the aircraft under the spherical fragment killing element and the shock wave killing element with different explosion ratio distances;the different damage situations under the titanium alloy structural form were discussed;and finally analyzed Typical damage modes,damage transformation conditions and damage mechanisms of aircraft structures.The results show that in the case of joint damage from high-speed fragments and shock waves,the combat damage of the aircraft structure is highly related to the rendezvous conditions;under the pre-loading of the shock wave,a large-scale plastic deformation zone appears in the metal structure,and the form of post-fragment penetration damage is mostly shear.Injuries and lacerations.As the shock wave ratio distance increases,large-scale tearing and separation occurs in the metal structure.The strength of the metal structure under shock wave loading is significantly reduced,and the residual velocity and residual mass of the fragments are significantly higher than those of single penetration.The subsequent loading of the shock wave will cause secondary changes in the damage morphology of the breach caused by penetration,leading to edge tearing and crack expansion.The conclusions of this study can provide a reference for aircraft protective design and provide basic input for troops emergency repair drills and battle damage preset.