在前方飞行中重叠螺旋的噪音模式的特征)
Burak Buda Turhan1, Hasan Kamliya Jawahar1, Djamel Rezgui1
1Department of Aerospace Engineering, University of Bristol, Bristol BS8 1TR, United Kingdom.
The Journal of the Acoustical Society of America
|April 14, 2025
概括
电动飞机中的重叠螺旋会增加噪音,特别是音调噪音. 侧面分离是管理这一问题的关键,在螺旋直径间隔40%时观察到显著的噪声增加.
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
- 可持续航空 可持续航空
背景情况:
- 分布式电推进 (DEP) 对于可持续航空至关重要.
- 在DEP系统中非传统的转子放置可能会导致噪音污染增加.
- 了解螺旋相互作用对于降低噪音至关重要.
研究的目的:
- 实验性地研究重叠螺旋的声学性能.
- 为了确定侧向和轴向分离对噪声水平的影响.
- 确定主要的噪声贡献者和影响因素.
主要方法:
- 进行了空声风洞实验.
- 采用了一种带有五叶片螺旋的双侧螺旋配置.
- 在不同的入流条件和旋转速度下分析了噪声水平.
主要成果:
- 音调噪声是导致声压水平升高的主要原因.
- 噪音水平对侧向螺旋的分离非常敏感.
- 螺旋直径的大约40%的横向距离显著提高了14-18dB的音调噪声.
结论:
- 侧面分离距离是螺旋声学行为的主导因素.
- 刀片-和刀片-唤醒相互作用是噪音的主要驱动因素.
- 轴间的分离对声学性能有次要影响.
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