飞机典型结构件的模拟战伤试验及数值模拟

【作者】 展全伟；

【导师】 郭伟国；

【作者基本信息】 西北工业大学 ， 固体力学， 2005， 硕士

【摘要】 在战争中,航空器由于受爆炸碎片、弹丸等外来物的打击而造成不可避免的结构损害并导致其丧失作战功能。近年来,随着飞机设计理论的发展,一方面从设计上提高飞机结构在撞击载荷作用下的高生存力,另一方面建立完善的损伤评估理论和技术,以便为实时抢修提供理论指导并进行快速抢修。在作战时期快速抢修并使飞机恢复作战能力显得尤为重要,所以研究建立完善的损伤理论和技术对空军来说有着十分重要的现实意义。 为了研究飞机典型结构件在常见弹丸打击下的损伤,本文选用了选用了四种典型的飞机结构件,其中一种3mm厚蒙皮结构,两种加筋结构和一种夹芯结构。采用试验和数值模拟相结合的方法,研究其在12.7mm标准机枪子弹弹丸射击下的损伤。 通过试验研究,一个由高速气炮,弹体与弹托分离机构、连续位移激光测速装置和弹丸回收装置被建立并有效的用于本文的弹丸正撞击试验。通过对四边固支的3mm厚蒙皮用12.7mm直径弹丸进行从速度从约60到300m/s的正撞击试验,得出了弹丸速度与靶板损伤尺寸的关系、弹丸速度与板件上应变变化的关系,弹丸剩余速度随弹丸撞击速度变化的关系。同时还对蒙皮板材料LY12-CZ进行了动态性能测试,并将测试结果用于数值模拟。最后利用DYNA3D程序对单蒙皮及其两种加筋板进行了弹击数值模拟,模拟结果与弹击结果比较吻合。更多还原

【Abstract】 In the combat action, the fighter plane often suffers the unavoidable structure damage, and even leads to fighting performance losing. The most damages are due to the impact of the debris or bullets. In the recent years, with the new design theory, the high survival design concept has been introduced into the aircraft design. At the same time, to achieve real time and quick repair for the damage of the aircraft, aircraft battle damage assessment and repair (ABDAR) program are being constructed. In the wartime, it is obviously important to make quick repair to recover the fighting performance. So it has the practical significance to construct the battle damage evaluation theory and technique for the air force.To investigate the damage behavior of a typical aircraft skin to a general projectile impact, four kinds of LY12-cz plates with thickness 3mm and reinforced aircraft skins are shoot by the projectile impact. In the present paper, a Test-Simulation method was adopted to investigate the damage modes of these skins to a projectile impact with 12.7mm diameter.During testing process, an effective testing system of simulating battle damage has been developed. It consists of high pressed air-gun, an assembled projectile body and bullet-shoe design, an instantaneous velocity measurement system with laser and lens, set-up frame for the specimens, and the projectile trap box. First, LY12-cz plate with thickness 3mm are fixed around, and shoot by the projectile under the velocities varied from 60 to 300m/s. Second, reinforced aircraft skins are tested by the same process as LY12-CZ plates, the relations of the bullet velocity and plate damage size, the bullet velocity and the plate strain, the bullet velocity and the bullet residual velocity are developed. Also the dynamic mechanical capability test of the cover material LY12-cz is carried and the test result is used in the numerical simulation. The numerical simulations are performed according to the test, and the results are compared with the testing results. It shows that, the simulation technique developed in the present paper is effective to simulate battle damage of the aircraft.更多还原