Effects of axial distance on the noise characteristics of contra-rotating coaxial rotors with identical/different rotor diameters

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics Pub Date : 2025-08-29 DOI:10.1016/j.apacoust.2025.111027

Boyang Jia, Gaohua Li, Zifei Yin, Xiaoqing Qiang, Weipeng Li

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引用次数: 0

Abstract

The axial distance between the upstream and downstream rotors is a critical installation parameter, affecting the aerodynamic and aeroacoustic performances of contra-rotating coaxial rotors. In this study, we investigate the effects of axial distance on the noise characteristics of contra-rotating coaxial rotors with identical and different diameters, by using 20″ and 16″ diameter rotors and adjusting the axial distance to the rotor diameter (

z / D

) within a large range of

0.1 - 0.6

. Results show that the configurations with identical rotor diameter exhibit the best aerodynamic efficiency and lowest noise level at

z / D \approx

0.3-0.4. Installation of a smaller rotor in the upstream results in a significant reduction of the overall sound pressure levels. Details on the noise directivity, features of the tonal and broadband noise, and noise generation mechanisms are discussed with separations of acoustic spectra at different axial distances.

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轴向距离对相同/不同转子直径对转同轴转子噪声特性的影响

上游和下游转子之间的轴向距离是一个关键的安装参数，影响对转同轴转子的气动和气动声学性能。在本研究中，我们采用20个″和16个″直径的转子，并在0.1 ~ 0.6的大范围内调整轴向距离与转子直径（z/D），研究轴向距离对相同和不同直径的对转同轴转子噪声特性的影响。结果表明：在z/D≈0.3 ~ 0.4范围内，转子直径相同的构型气动效率最佳，噪声最低；在上游安装一个较小的转子可以显著降低整体声压级。通过不同轴向距离的声谱分离，详细讨论了噪声的指向性、音调和宽带噪声的特征以及噪声的产生机制。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Applied Acoustics 物理-声学

CiteScore

7.40

自引率

11.80%

发文量

618

审稿时长

7.5 months

期刊介绍： Since its launch in 1968, Applied Acoustics has been publishing high quality research papers providing state-of-the-art coverage of research findings for engineers and scientists involved in applications of acoustics in the widest sense. Applied Acoustics looks not only at recent developments in the understanding of acoustics but also at ways of exploiting that understanding. The Journal aims to encourage the exchange of practical experience through publication and in so doing creates a fund of technological information that can be used for solving related problems. The presentation of information in graphical or tabular form is especially encouraged. If a report of a mathematical development is a necessary part of a paper it is important to ensure that it is there only as an integral part of a practical solution to a problem and is supported by data. Applied Acoustics encourages the exchange of practical experience in the following ways: • Complete Papers • Short Technical Notes • Review Articles; and thereby provides a wealth of technological information that can be used to solve related problems. Manuscripts that address all fields of applications of acoustics ranging from medicine and NDT to the environment and buildings are welcome.