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In this paper, a method to design bird-strike-resistant aircraft structures is presented and illustrated through examples. The focus is on bird strike experiments and simulations. The explicit finite element software PAM-CRASH is employed to conduct bird strike simulations, and a coupled Smooth Particles Hydrodynamic (SPH) and Finite Element (FE) method is used to simulate the interaction between a bird and a target structure. The SPH method is explained, and an SPH bird model is established. Constitutive models for various structural materials, such as aluminum alloys, composite materials, honeycomb, and foam materials that are used in aircraft structures, are presented, and model parameters are identified by conducting various material tests. Good agreements between simulation results and experimental data suggest that the numerical model is capable of predicting the dynamic responses of various aircraft structures under a bird strike, and numerical simulation can be used as a tool to design bird-strike-resistant aircraft structures. 相似文献
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飞机的鸟撞事故是一种突发性和多发性的飞行事故,轻则飞机受损,重则机毁人亡.在飞机设计过程中,为了通过严格的适航条例,需要进行大量的鸟撞试验.随着有限元理论和计算机软、硬件的发展,利用计算机仿真技术进行飞机结构的抗鸟撞设计分析可以减少试验数量或者加强试验针对性,提高试验效率.基于LS-DYNA软件和前处理软件HyperMesh,利用光滑粒子法(SPH)与有限元耦合算法,采用带失效模型的短梁单元模拟铆钉失效,对某型飞机垂尾前缘进行鸟撞分析.通过对应力和位移结果的分析以及对沙漏能的有效控制,表明本文提出的建模方法具有满足工程要求的准确性,符合适航条例的规定. 相似文献
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《中国航空学报》2023,36(5):328-343
On the windward side of an aircraft, the components with higher probability of impact with birds are the wing-type leading edge structures, such as the wing and tail. A study on the damage sensitivity of a wing-type leading edge structure under bird strikes was presented in this paper. First, a bird strike test was carried out on a wing. The principles of the bird strike test equipment and method were introduced in detail, including the bird strike test system, bird projectile production process and data acquisition system. The dynamic strain measurement results, the high-speed camera videos, and the final deformation and damage morphology observations of the structure were obtained. Based on the coupled Smooth Particle Hydrodynamics (SPH) - Finite Element Method (FEM), the commercial software PAM-CRASH was used to simulate the process of a bird strike with the wing. The good agreement between the finite element simulation results and the experimental results shows that the calculation method and the numerical model presented in this paper were reasonable. On this basis, wing-type leading edge structures can be designed by adding triangular support. The bird strike resistances of an original structure and improved structure were studied by numerical simulation. The calculated results show that the improved wing-type leading edge structure is less damaged than the original structure under bird strike. The improved leading edge structure satisfied the anti-bird strike airworthiness requirements, as the thickness of the triangular support was 1.2 mm, and the weight of the structure was reduced by 0.87 kg compared with the original structure. This indicated that the bird strike resistance of the improved structure is better than that of the original structure, and the improved design of the wing-type leading edge structure presented in this paper is reasonable. 相似文献
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Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics (SPH) method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing lead-ing edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi’s L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance (ANOVA) is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simu-lation is conducted under the optimal condition to show the improvement of performance of the wing structure. 相似文献
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有限元模拟鸟撞风扇叶片损伤成本高,为解决工程问题,采用经典叶栅鸟撞切割模型建立了鸟撞风扇叶片动载荷数学
模型,结合鸟撞部件试验结果,以拟合技术明确风扇叶片损伤程度与最大关键动载荷计算值间的函数关系,形成叶片损伤预测响
应面,实现对鸟撞风扇叶片损伤的快速预测,并建立基于响应面法的鸟撞风扇叶片损伤预测工作流程。结合涡扇发动机吞鸟试验
技术要求、风扇结构设计特征及已开展的鸟撞部件试验结果,建立叶片损伤预测响应面,初步识别2种鸟撞方案的径向弯曲、弦向
弯曲,并计算撕裂范围分别不超过0.3867和0.3941,撕裂与弦向弯曲相关性显著,呈抛物线变化趋势。结果表明:预测的损伤在可
接受的安全性水平范围内,预测方法能够识别损伤范围及趋势,可为后续鸟撞有限元模拟、试验策划、安全性分析、风扇叶片抗鸟
撞设计等工作提供量化的技术支持。 相似文献
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对弹性动力学的基本理论以及SPH(光滑粒子流体动力学)鸟体模型进行了介绍,并结合相关材料性能参数,以显式动态冲击有限元软件PAM-CRASH为平台,开展某大型民用客机机头顶部板结构抗鸟撞性能验证工作。并设计两种金属玻璃纤维材料作为优化材料,在不增加结构总重量的基础上通过比较结构吸能效果对材料铺层进行优化,选取出抗鸟撞性能最佳的材料供工程设计参考。 相似文献
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民用飞机方向舵结构通常位于垂尾后部,通过连接铰链与垂直安定面后缘相连,并通过作动器驱动其偏转,从而为飞机提供偏航力矩。对民用飞机方向舵鸟撞相关适航条款要求进行了分析,明确了方向舵抗鸟撞需要满足的具体要求。在完成上述工作后,对某型民机方向舵的抗鸟撞性能进行了全面的评估。首先通过工程算法,初步评估了该方向舵不同偏角下的鸟体撞击力,并以此为依据筛选出了鸟撞的严酷工况,避免了大量计算方向舵不同偏角的鸟撞情况,从而大大降低了仿真分析的工作量。通过SPH方法,使用PAM-Crash软件对方向舵结构进行了抗鸟撞分析,得到了方向舵翼面本体结构的损伤情况、连接铰链的受载情况和方向舵作动器的受载情况,并以此为依据,完成了对方向舵抗鸟撞性能的完整评估。 相似文献
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基于ANSYS Workbench鸟撞飞机风挡有限元分析 总被引:1,自引:0,他引:1
利用ANSYS Workbench三维有限元软件,建立了鸟撞飞机风挡的力学分析模型,形成了一套完整合理的鸟撞飞机动态响应分析方法。其中,对模型建立和约束施加等提出了简便的处理方法,并且进行了比较详细的描述。通过有限元分析模拟计算鸟撞飞机前风挡的动态响应,得出了风挡的应力、位移及其分布规律,并与试验结果进行比较,两者吻合较好,可为新型风挡结构设计提供参考。 相似文献
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In order to examine the process of a rotary engine primary compressor impacted by bird, a finite element model of a bird impacted on plate is developed with the explicit code PAM-CRASH. The smooth particles hydrodynamic (SPH) method is used to simulate the bird because of the SPH method showing no signs of instability and correctly modeling the breaking-up of the bird into particles. Good agreement between the simulation results and experimental results indicates that the numerical method of bird strike used in the present paper is reasonable. Then a rotary engine primary compressor impacted by three different configurations bird named straight-ended cylinder bird, quadrangular bird, hemispherical-ended bird are investigated using the numerical simulation method. It is found that the whole process of bird strike sustained about 3.5 ms and the bird is slashed by blade during the strike. The geometry configuration of bird affected the displacement and von Mises stress of some blades severely, just because the breaking bird’s mass is affected by the bird’s configuration. In the event of bird striking on the site of"up"some blades may develop plastic deformation and it is very adverse for the safety work of the engine. 相似文献
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典型前缘结构抗鸟撞性能改进研究 总被引:4,自引:1,他引:3
针对某典型前缘结构,研究了使用纤维金属层板(Fibre Metal Laminates,FMLs)蒙皮进行抗鸟撞设计的可行性。以显式动态冲击分析程序PAM-CRASH为平台,结合由鸟撞平板试验结果验证的鸟体本构模型参数,建立了鸟撞前缘结构数值模型。通过计算研究了使用不同蒙皮(铝合金、FMLs)的前缘结构在鸟撞作用下的变形破坏模式及吸能效果。结果表明:采用适当铺层的FMLs蒙皮可以有效地提高前缘结构的抗鸟撞性能。研究结论对飞机结构的抗鸟撞研究具有一定的参考价值。 相似文献
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用SPH和有限元方法研究鸟撞飞机风挡问题 总被引:4,自引:0,他引:4
鸟与飞行中的飞机相撞是飞机结构损坏的重要因素,严重时会引发机毁人亡的灾难性事故。对高速低空飞行的军用飞机而言,风挡部分抗鸟撞的研究对保证飞行安全尤其重要。基于飞机圆弧风挡受鸟体撞击的实验观察,建立了国产某型军用飞机圆弧风挡及鸟体的计算模型,采用LS-DYNA3D中有限元和光滑粒子流体动力学(SPH)耦合的数值分析方法,对某飞机圆弧风挡受鸟体撞击的过程进行了数值模拟。计算结果得到了风挡结构的变形、位移和应变等几方面的数据,与实验结果基本吻合。同时,给出了500~650km/h速度范围内的撞击力和应力时程曲线、风挡发生破坏的临界撞速、圆弧风挡经受鸟体撞击时发生破坏的可能位置及其破坏方式。最后,与鸟体采用任意拉格朗日(ALE)和无网格伽辽金方法(EFG)进行了对比,验证了SPH方法在分析鸟撞问题中的优越性。研究结果为风挡的安全设计和研制新机型提供了有价值的数据。 相似文献
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鸟体撞击结构过程的相似律研究(英文) 总被引:2,自引:0,他引:2
Li Yulong* Zhang Yongkang Xue Pu School of Aeronautics Northwestern Polytechnical University Xi’an China 《中国航空学报》2008,21(6):512-517
With dimensional analysis and similarity theory, the model similarity law of aircraft structures trader bird impact load is investigated. Numerical calculations by means of nonlinear dynamic software ANSYS/LS-DYNA are conducted on the finite element models constructed with different scaling factors. The influence of strain rate on the model similarity law is found to be dependent on the strain rate sensitivity of materials and scale factors. Specifically, materials that are not sensitive to strain rate obey the model similarity law in the bird impact process. The conclusions obtained are supposed to provide a theoretical basis for the experimental work of bird impact on aircraft structure. 相似文献
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冒颖 《民用飞机设计与研究》2020,(1):12-15
指形罩结构位于吊挂前缘,作为动力装置整流罩体的一部分,为吊挂及发动机提供气动外形,并为燃油、液压、电气、环控等系统管路提供保护和通路。指形罩的位置及功能决定了其结构必须满足鸟撞要求,承受鸟体撞击后不能影响飞机安全。通常采用鸟撞试验对指形罩结构抗鸟撞性能进行适航验证。为了降低适航验证周期和成本,一般通过鸟撞分析来降低取证试验的撞击点数量。介绍了一种吊挂指形罩鸟撞分析过程和方法,并对分析方法进行了工程试验验证,得到一种可靠的指形罩鸟撞分析方法,为类似的飞机整流结构的鸟撞分析提供了参考。 相似文献
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飞机结构的抗鸟撞性能对于飞行安全有着直接的联系,鸟撞事故一旦发生,对飞机结构、设备的破坏作用往往极为严重。针对Glare层合板材料进行了抗鸟撞分析,利用有限元方法,采用显式碰撞动力分析软件PAM-CRASH,对四种不同纤维铺层角的Glare层合平板进行了抗鸟撞仿真分析,比较选取了最优的纤维铺层角;设计了全尺寸的机翼前缘模型,对4/3和3/2两种构型的Glare层合蒙皮进行了抗鸟撞仿真。结果表明4/3构型的Glare层合蒙皮的抗鸟撞效果最好,该构型将被进一步应用于机翼抗鸟撞试验件的设计中。 相似文献