Abstract This research concerns the crashworthiness study and enhancement of commercial aircraft fuselage structures by incorporating crushable hybrid energy absorbers to work as vertical struts. To assess their contribution on a representative aircraft structure, a numerical simulation of a Boeing 737-200 drop test is developed and validated with experimental data available in the literature. The fuselage section is then simulated both with and without the fuel tank, showing more harmful effects for the latter scenario. The numerical model accurately captures the experiment’s collapse process with low artificial energy ratios. Later, four vertical hybrid energy absorbers designed for programmed and progressive collapse, are added in the cargo compartment, connecting the underfloor beams and the frames. Different designs and positions are studied, combining aluminum tubes with square and circular cross-sections, filled with a core made from a GFRP skeleton and foam extrusions. Acceleration graphs show a reduction in passenger injury levels from severe to moderate according to an Eiband diagram when energy absorbers are fitted. Energy trends from the hybrid absorbers are also monitored, with dissipation of up to 10 kJ of the fuselage’s kinetic energy through plastic deformation and collapse. Results also show a significant improvement on the global crashworthiness of the fuselage, leading to an increase in plastic dissipation by the frames from 76 kJ to 122 kJ and a reduction on the accelerations up to 50% when the energy-absorbing structures are added.

中文翻译：

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民用飞机机身设计中作为垂直支柱的混合吸能器的耐撞性研究

摘要 本研究涉及通过将可压碎的混合吸能器用作垂直支柱来研究和增强商用飞机机身结构的耐撞性。为了评估它们对代表性飞机结构的贡献，我们开发了波音 737-200 跌落测试的数值模拟，并使用文献中可用的实验数据进行了验证。然后对有和没有油箱的机身部分进行了模拟，显示了后一种情况的更多有害影响。该数值模型以较低的人工能量比准确地捕捉了实验的坍塌过程。后来，在货舱中增加了四个垂直混合能量吸收器，用于程序化和渐进式折叠，连接地板下的横梁和框架。研究了不同的设计和位置，结合方形和圆形横截面的铝管，填充由 GFRP 骨架和泡沫挤压制成的芯。根据 Eiband 图，加速度图显示了当安装了能量吸收器时，乘客受伤程度从重度降低到中度。来自混合吸收器的能量趋势也受到监控，通过塑性变形和坍塌，机身动能的耗散高达 10 kJ。结果还表明，机身的整体耐撞性显着提高，导致框架的塑料耗散从 76 kJ 增加到 122 kJ，并且当添加能量吸收结构时，加速度降低了 50%。根据 Eiband 图，加速度图显示了当安装了能量吸收器时，乘客受伤程度从重度降低到中度。来自混合吸收器的能量趋势也受到监控，通过塑性变形和坍塌，机身动能的耗散高达 10 kJ。结果还表明，机身的整体耐撞性显着提高，导致框架的塑料耗散从 76 kJ 增加到 122 kJ，并且当添加能量吸收结构时，加速度降低了 50%。根据 Eiband 图，加速度图显示了当安装了能量吸收器时，乘客受伤程度从重度降低到中度。来自混合吸收器的能量趋势也受到监控，通过塑性变形和坍塌，机身动能的耗散高达 10 kJ。结果还表明，机身的整体耐撞性显着提高，导致框架的塑料耗散从 76 kJ 增加到 122 kJ，并且当添加能量吸收结构时，加速度降低了 50%。通过塑性变形和坍塌耗散高达 10 kJ 的机身动能。结果还显示机身的整体抗撞性显着提高，导致框架的塑料耗散从 76 kJ 增加到 122 kJ，并且当添加能量吸收结构时加速度降低高达 50%。通过塑性变形和坍塌耗散高达 10 kJ 的机身动能。结果还表明，机身的整体耐撞性显着提高，导致框架的塑料耗散从 76 kJ 增加到 122 kJ，并且当添加能量吸收结构时，加速度降低了 50%。