模拟的次声波喷气噪声声源的声学特征使用球体波
Christian Dreier1, Xenia Vogt2, Wolfgang Schröder2
1Institute for Hearing Technology and Acoustics, RWTH Aachen University, Germany.
The Journal of the Acoustical Society of America
|July 12, 2023
概括
本研究介绍了喷气式噪声的简化球形等效源模型,这对于早期飞机设计至关重要. 它通过识别九个主要的基本源来量化噪声,帮助计算流体动力学模拟.
科学领域:
- 声学和空气动力学
- 计算流体动力学的流体动力学.
背景情况:
- 飞机噪音,特别是来自低音喷气机的噪音,是一个重要的环境问题.
- 早期将近场流量模拟与定量声音数据相结合,对于飞机设计至关重要.
- 一个关键的挑战是有效地将近场噪声数据与远场声波辐射 (包括反射) 联系起来.
研究的目的:
- 为喷气噪声开发一个计算效率高的球形等效源模型.
- 为了简化近场流量数据和远场声学预测之间的接口.
- 为大规模计算流体动力学 (CFD) 模拟提供一个可用的格式.
主要方法:
- 使用球体 (SH) 系数计算一个球体等效源模型.
- 来自虚拟麦克风阵列的声压数据的球形汉克尔外推.
- 在流场内确定声源区域半径.
主要成果:
- 声源区域仅限于半径大约是喷嘴直径的五倍,靠近潜在核心的尽头.
- 球体波变换确定了九个基本源作为喷气噪声能量的主要贡献者.
- 一个简化,低复杂度的球形等效源模型成功计算出来.
结论:
- 开发的球形同等源模型为喷气噪声分析提供了一种计算效率高的方法.
- 这种模型有助于将声学预测整合到飞机设计的早期阶段.
- 这些发现为将喷射噪声建模纳入先进的CFD模拟提供了一个方便的格式.
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