大柔性飞机着陆响应弹性机体模型

对大展弦比、小弦长差、细窄机身结构特征的飞机,建立了着陆撞击分析时的自由-自由梁弹性机体模型,给出了自由-自由梁弯曲振动的一个近似解,并与实测值进行了对比,结果表明这个近似解具有较大的适用性.介绍了飞机机体刚体模态和一阶弯曲振动模态的飞机机体二质量块等效模型,研究了最大起飞质量及最小飞行质量2种情形下着陆时的机体弹性特征,探讨了弹性飞机起落架设计与刚性飞机相比在技术上的重大变化,为起落架设计中考虑飞机弹性影响提供了简化模型、直观概念和可靠依据.

Elastic model for flexible airplane landing impact analysis

A free-free beam model for flexible airplane is used to describe a large wingspan-chord ratio, little chord difference, and small width body structure of high-altitude long-endurance unmanned airplane. Bending vibration equation of the free-free beam is solved approximately and the solution is compared with experimental data. The results show that this approximate solution is applicable. Equivalent tow mass model is introduced to simulate rigid mode and first bending vibration mode of the flexible airplane.The flexible feature of high-altitude long-endurance unmanned airplane in landing with maximum take-off mass or minimum flying mass is studied. Improvement of landing gear design technology of flexible airplane is approached. This study provides simple models, audiovisual concepts and reliable basic for flexible airplane landing gear design.