相同步相邻螺旋的声学特性
Burak Turhan1, Hasan Kamliya Jawahar1, Abhishek Gautam1
1Department of Aerospace Engineering, University of Bristol, Bristol BS8 1TR, United Kingdom.
The Journal of the Acoustical Society of America
|May 14, 2024
概括
在同步螺旋中调整叶片相角可以显著降低噪声. 90°的相角提供最大的噪声减弱,使叶片通过频率噪声降低高达24dB.
科学领域:
- 声学 声学 在声学方面
- 空气动力学 在空气动力学.
- 推进系统 推进系统
背景情况:
- 分布式电推进 (DEP) 系统使用多个同步螺旋.
- 螺旋产生的噪音是飞机和其他应用中的一个重要问题.
- 控制螺旋噪音对于环境和运行原因至关重要.
研究的目的:
- 为了研究叶片相位角度对相邻电子同步螺旋噪声减弱的影响.
- 为了量化不同前进比和相角的噪声降低.
- 为了确定DEP系统中噪声控制的最佳相角.
主要方法:
- 在空气声学风洞中进行了声学测量.
- 两个相邻的,双叶片螺旋被电子同步.
- 从0°到90°的相对相角 (Δψ) 在各种前进比 (J = 00.73) 和固定旋转速度 (5000rpm) 下进行了测试.
主要成果:
- 一个相对相位角 Δψ = 90° 给出了最大的噪声降低.
- 在J=0时,观察到第一个叶片通过频率 (BPF) 降低8dB,整体声压水平 (SPL) 降低2dB.
- 在入流条件下 (J > 0),Δψ = 90°导致在第一个BPF下大约减少24dB,与Δψ = 0°相比,SPL总体减少6dB.
- 在BPF观察到噪声导向性和音调噪声的显著降低.
结论:
- 叶片相角是DEP系统中控制螺旋噪声的有效方法.
- 90°相对相位角度是噪声减弱的最佳选择.
- 研究结果为设计更安静的电动推进系统提供了关键的见解.
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