多旋翼飞机的宽带噪声调制)
Ze Feng Ted Gan1, Vitor Tumelero Valente1, Kenneth S Brentner1
1Department of Aerospace Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
The Journal of the Acoustical Society of America
|February 7, 2025
概括
研究人员研究了在六合飞机无人机中的宽带噪声调制. 他们发现,控制转子相位可以降低噪音,类似于它如何降低噪音.
科学领域:
- 声学 声学 在声学方面
- 航空航天工程 航空航天工程
- 振动分析 振动分析
背景情况:
- 转子宽带噪声通常在长时间尺度上进行分析,忽视调制效应.
- 宽带噪声与叶片通道频率的调制对于直升机和风力轮机的感知噪声至关重要.
- 无人机等多旋翼飞机中的宽带噪声调制仍未得到充分研究.
研究的目的:
- 调查六直升机无人机 (UAV) 中的宽带噪声调制.
- 为了确定旋转机间相位关系对宽带噪声调制的影响.
- 探索同步阶段控制在多旋翼飞机中减轻宽带噪声调制的潜力.
主要方法:
- 在六直升机无人机上进行了飞行测试和无声室实验.
- 测量宽带噪声水平和分析调制特征.
- 研究了旋转机之间的不同亚齐图斯相位偏移的影响.
- 计算了对非同步转子的调制深度的概率分布.
主要成果:
- 在测试期间,在六直升机无人机中观察到显著的宽带噪声调制.
- 宽带噪声调制的幅度直接取决于旋转机之间的亚齐木斯相位偏移.
- 非同步转子呈现时间变化的相位偏移,导致随机调制深度.
- 成功计算了调制深度的概率分布.
结论:
- 宽带噪声调制是多旋转机飞机声学的一个重要因素.
- 旋转器同步阶段化为减少宽带噪声调制提供了一个可行的策略,类似于音调噪声控制.
- 了解来自单个转子的宽带噪声调制的总和对于预测整体噪声特征至关重要.
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