阶段同步对分布式螺旋的音调声音导向性的影响
A Zarri1,2, F de Prenter1, F Avallone3
1Department of Flow Physics and Technology, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands.
在分布式电力推进中,转子同步可以减少噪音. 调整相邻转子的相对相位角度可以显著改变噪声导向性和声压水平,为降低噪声提供了一个有前途的策略.
科学领域:
- 航空航天工程 航空航天工程
- 声学 声学 在声学方面
- 计算流体动力学的流体动力学.
背景情况:
- 分布式电推进 (DEP) 系统正在探索降低噪音.
- 转子相同步是一种拟议的降噪策略.
- 在DEP中,空气动力学相互作用及其对远场噪声的影响尚不清楚.
研究的目的:
- 研究相对相位角对DEP中音调噪声导向性的影响.
- 了解导致噪声产生和传播的空气动力学机制.
- 量化由于相位同步而导致的噪声水平变化.
主要方法:
- 使用了格子博尔茨曼非常大的模拟器 (VLES).
- 模拟了三个相邻的共旋转转子,其辐射间距较小 (直径为2%).
- 分析了不同相对相位角度的音调噪声导向性.
主要成果:
- 靠近引起的空气动力学相互作用是音调噪声的主要来源.
- 机制包括输入扭曲和相角依赖的叶片尖端效应.
- 在零和相反相位条件之间,沿入流方向观察到高达4.5dB的声压水平变化.
- 声学干扰显著改变噪声的方向性,使得在某些方向几乎可以取消噪声.
结论:
- 转子相同步是DEP系统降噪的可行策略.
- 控制相对相位角可以将噪声从敏感区域转移.
- 对空气动力学相互作用的进一步研究对于优化DEP噪声性能至关重要.
更多相关视频
08:32Assembly and Characterization of an External Driver for the Generation of Sub-Kilohertz Oscillatory Flow in Microchannels
Published on: January 28, 2022
08:28Synthesis of Phase-shift Nanoemulsions with Narrow Size Distributions for Acoustic Droplet Vaporization and Bubble-enhanced Ultrasound-mediated Ablation
Published on: September 13, 2012
相关概念视频
Frequency-Domain Interpretation of PD Control
The proportional control gain, combined with the...
Sound Waves: Interference
Time and frequency -Domain Interpretation of Phase-lead Control
The design of phase-lead control involves the strategic placement of poles and zeros to balance steady-state error and system...
Phase-lead and Phase-lag Controllers
Interference: Path Lengths
Two special sources may be considered when they are in phase. This can be easily achieved by feeding the two sources from the same source. An example would be synchronizing the two speakers by feeding them with the same source, such as the sound waves produced by a tuning fork. This setup ensures that the two sources have the same frequency and are...
Time-Domain Interpretation of PD Control
Consider the example of control of motor torque. Initially, a positive...
