一个实验室规模的燃烧后喷气式噪声装置的相似性光谱分析
Ashwin Kumar1, Joseph W Meadows1, Kent L Gee2
1Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24060, USA.
The Journal of the Acoustical Society of America
|December 2, 2025
概括
这项研究成功地在实验室环境中复制了全尺寸的燃烧后喷射光谱. 这些发现验证了实验室规模的后燃机声学测试,用于未来的研究和开发.
科学领域:
- 声学 声学 在声学方面
- 航空航天工程 航空航天工程
- 流体动力学 流体动力学
背景情况:
- 燃烧后喷气机对于高推力飞机至关重要,但会产生相当大的噪音.
- 预测后燃烧器声学是复杂的,因为流结构.
- 现有的相似性模型需要对实验数据进行验证.
研究的目的:
- 为了比较实验室规模的后燃喷气光谱与全尺度 (FS) 后燃喷气.
- 评估Tam的相似性模型对后燃烧器声学的适用性.
- 为了确定微尺度相似性光谱 (FSS) 和大尺度相似性光谱 (LSS) 在模拟后燃烧器噪声中的有效性.
主要方法:
- 在FS喷气机 (∼6) 相关的总温度比率下运行实验室规模的后燃设备.
- 从喷嘴出口的63个直径收集远场声学数据.
- 拟合相似性光谱 (FSS和LSS) 以匹配测量的光谱形状,峰值频率和滚动.
- 在各种侧线角度分析光谱特征.
主要成果:
- 实验室规模的后燃喷气光谱成功地重现了FS喷气的光谱特征.
- FSS和LSS的组合有效地建模了过渡区域 (90°107.5°).
- 仅LSS就模拟了在峰值声压水平辐射附近的光谱,而FSS则足以用于侧线角度.
- 塔姆的相似性模型未能预测观察到的双峰,并显示了峰值辐射区域以外的高频斜率不匹配.
结论:
- 实验室规模的后燃机设备可以准确地复制FS后燃机喷气声学.
- 塔姆的相似性模型在预测复杂的光谱特征,如双峰和高频倾斜等方面存在局限性.
- 特定的FSS和LSS方法对于后燃烧器噪声辐射的不同区域是有效的.
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