非线性气弹性建模和分析一个几何非线性机翼的组合不稳定的截面和起重线空气动力学
Sanuja Jayatilake1, Mark Lowenberg1, Benjamin K S Woods1
1School of Civil, Aerospace and Design Engineering, University of Bristol, Bristol, UK.
概括
这项研究提出了灵活翼的新型非线性空气弹性模型,准确预测飞和极限周期振荡. 该模型经过实验验证,有助于理解气弹性现象和设计控制规律.
科学领域:
- 航空工程 航空工程
- 计算流体动力学的流体动力学.
- 结构动力学 结构动力学
背景情况:
- 空气弹性对于飞机的安全性和性能至关重要.
- 灵活的翅膀中的几何非线性效应显著影响了气弹性行为.
- 精确的模拟不稳定的空气动力学与有限的跨度效应是具有挑战性的.
研究的目的:
- 开发一种新的,几何非线性气弹性模型,用于悬臂弹性翼.
- 为了捕捉不稳定的空气动力学和有限的跨度效应.
- 通过实验数据验证模型并分析空气弹性现象.
主要方法:
- 结构模型的切比舍夫 - 里茨方法.
- ONERA不稳定的空气动力学配方与升降线方法相结合.
- 作为连续状态空间模型和数值连续的表述.
主要成果:
- 该模型准确地预测了分叉特性和空气弹性模式.
- 波动开始速度预测在实验值的5%以内.
- 波动后极限周期振荡 (LCO) 正确捕获.
结论:
- 开发的模型有效地模拟了灵活的翅膀中的非线性气弹性行为.
- 模型的准确性对空气动力学系数敏感,需要校准.
- 这项研究为分析气弹性现象和设计灵活翼的控制规律提供了有价值的工具.
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