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基于任务的最佳变形参数,用于带有合并弦和扭曲变形的旋转机
Rohin Kumar Majeti1, Stephan Benz2
1German Aerospace Center (DLR), Braunschweig, Germany.
Open research Europe
|August 30, 2023
概括
现在,直升机的旋翼叶片可以在飞行中改变形状. 结合和弦延长和扭曲变形,可以显著提高不同任务的性能,特别是在悬浮和低速飞行期间.
科学领域:
- 航空航天工程 航空航天工程
- 计算流体动力学的流体动力学.
- 旋翼飞机航空动力学 旋翼飞机航空动力学
背景情况:
- 固定几何直升机旋翼叶片在不同的飞行条件下是不理想的.
- 不同的飞行模式 (低速与高速) 需要不同的叶片几何形状以获得最佳性能.
- 变形技术提供了一种解决方案,通过使旋翼叶片在飞行过程中调整形状.
研究的目的:
- 调查直升机转子变形概念的最佳几何参数.
- 为了评估结合和弦延伸和扭曲形态的性能好处.
- 在各种直升机任务配置中分析变形叶片性能.
主要方法:
- 利用粒子优化 (PSO) 来确定最佳的变形参数.
- 研究了两个变形概念:线性可变的和弦延伸和基于扭矩管的扭转.
- 在三个任务配置中,针对单一 (动力) 和多目标 (动力,扭矩,振动) 场景,优化了转子性能.
主要成果:
- 合并和弦和扭曲变形实现了比基线刀片在完整任务中的6.8%的性能改进.
- 在悬浮和低速飞行 (μ = 0.14) 期间,性能增长达到了13%.
- 尽量减少弹性扭转和转子振动的处罚,同时提高整体性能.
结论:
- 弦和扭动都对旋翼叶片效率至关重要.
- 结合和弦和扭曲变形概念,可以提供超越个人贡献的协同性能效益.
- 适应性转子叶片几何是最大限度地提高直升机在任务范围内的性能的关键.
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