Influence of bird yaw/pitch orientation on bird-strike resistance of aircraft structures
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摘要: 低于现行标准规定能量的大量鸟撞事故中,航空结构仍然发生实质性破坏的情况,说明只考虑鸟体的质量和速度不足以保证飞机安全。本文中针对弹性平板、雷达罩及机翼前缘等飞机典型结构,开展了不同姿态鸟体的鸟撞分析研究。分析结果发现,鸟体姿态对结构的抗鸟撞性能有比较显著的影响,不同的结构特点反映的响应规律也不同:对吸能结构,姿态角越大,吸收的能量越多,被保护的结构就越安全;而对承力结构,姿态角越大,高应力区域越大,结构就越危险。因此,在结构的抗鸟撞安全性评估中,除了完成特定姿态鸟体的鸟撞实验,针对危险工况还应通过数值分析评估不同鸟体姿态的结构撞击响应,进一步确保结构的抗鸟撞能力。Abstract: There have been numerous bird-strike accidents in which substantial damage to the airframe occurred even though the striking force involved did not reach the energy standard currently required, showing that only taking mass and velocity into account in bird-strike prevention cannot guarantee airframe safety. In order to find out the effect of the bird yaw/pitch orientation on the safety of different aircraft structures, the dynamic responses on the panel, the radome, and the plane wing's leading edge were investigated. The results show that the bird-strike resistance of the structure is significantly affected by the bird's yaw/pitch orientation, and different structural characteristics lead to different dynamic responses. The greater the attitude angle, the more energy absorbed for the energy-absorbing structure, and accordingly the safer the protected structure; for the load-bearing structure, the greater the attitude and the larger the high stress area on the structure, the more vulnerable the structure. Therefore, in the evaluation of aircraft structures' bird-strike resistance capability, apart from doing the bird-strike experiment, it is also necessary to investigate different responses of various bird yaw/pitch orientations to the hazardous parts of aircraft structures through numerical simulation.
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Key words:
- bird-strike /
- bird yaw/pitch attitude /
- impact effects /
- energy absorption /
- radome /
- plane wing's leading edge
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表 1 不同鸟体姿态在监测点应力与0°的偏差
Table 1. Deviation of panel stress between 0° orientation and the others
α/(°) ηmax/% ηA/% ηB/% ηC/% ηD/% ηE/% 22.5 -4.1 2.0 -0.6 2.6 -1.5 -1.3 45.0 -2.5 0.8 1.0 11.7 6.1 0 67.5 1.4 8.5 4.0 28.9 19.2 18.7 90.0 3.6 25.5 7.3 109.7 75.8 55.0 表 2 非金属材料参数
Table 2. Parameters of non-metallic material
量和单位 玻璃纤维增强材料 蜂窝材料 ρ/(kg·m-3) 1 900 64 E11/MPa 27 300 - E22/MPa 26 500 - E33/MPa - 71.68 G12/MPa 4 390 - G13/MPa - 76.11 G23/MPa - 35.44 X1c/MPa 309 - X1t/MPa 642.9 - X2c/MPa 363 - X2t/MPa 614 - S12/MPa 221 - X3c/MPa - 3.84 X3t/MPa - 4.32 X13/MPa - 2.14 X23/MPa - 2.01 表 3 金属材料参数
Table 3. Parameters of metallic material
材料 ρ/(kg·m-3) E /GPa σs/MPa εf 7050-T7451 2 820 70 448 0.095 LY12-CZ 2 780 71 424 0.127 2024-T351 2 780 70 310 0.089 7075-T7351 2 800 72 395 0.086 -
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