宽带噪声的数值分析由一个带有跨度变化的前沿边缘的气翼产生
Lei Wang1, Xiaomin Liu1, Chenye Tian1
1Department of Fluid Machinery and Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Biomimetics (Basel, Switzerland)
|April 26, 2024
概括
领先的纹能够有效地降低空气动力学噪音. 双波长设计比单波长设计提供更好的降噪,特别是在特定的尖端到根的比率.
科学领域:
- 空气动力学 航空动力学
- 声学 声学 在声学方面
- 流体力学 流体力学 流体力学
背景情况:
- 来自前沿的空气动力学噪声是各种工程应用中的一个重要问题.
- 了解和减轻这种噪音对于提高效率和减少环境影响至关重要.
- 前边的纹已经显示出降噪的潜力,但最佳设计需要进一步研究.
研究的目的:
- 为了研究不同尖端形状的有效性,以减少空气动力学噪音.
- 分析压缩参数 (频率,振幅,相位,形状因子,波长) 对噪声抑制的影响.
- 探索降噪的基本机制,包括相干扰和局部源切断效应.
主要方法:
- 使用Wiener-Hopf技术进行分析建模,用于对前沿噪声的单个目标参数化.
- 实施和分析四个不同的尖端形状.
- 参数研究形状因子,波长和振幅在不同的尖端到根的比率 (0.5,1,2).
主要成果:
- 一个双波长的正弦形形设计实现了相当大的噪声降低5.2dB的尖端到根的比率为2.
- 在最佳参数下,双波长纹与单波长设计相比,提供了额外的1.47dB的噪声降低.
- 具有小曲率的纹增强了用于低频噪声抑制的相干扰,而更尖的纹减少了高频噪声. 形的纹减少了根源声音源的强度.
结论:
- 最先进的,特别是双波长的正弦形设计,有效地减少了空气动力学噪声.
- 的有效性受其几何参数和尖端到根的比率的影响.
- 阶段干扰和局部源切断效应是降低噪声的关键机制,具有针对不同频段和噪声源的特定形.
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