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安装的GE F404喷气发动机的声音功率和声学效率
Matthew A Christian1, Kent L Gee2, Jacob B Streeter2
1Department of Mechanical Engineering, Brigham Young University, Provo, Utah 84602, USA.
JASA express letters
|July 5, 2023
概括
这项研究验证了用于GE-F404发动机测量的经典喷气噪声理论. 声音功率的变化与低音和超音速条件的第三功率规律的第八功率规律保持一致,尽管超音速的增加超过了预测.
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:
- 经典的喷气式噪声理论预测声音功率与速度的变化 (次声速的第八级,超声速的第三级).
- 将理论预测与现实世界发动机数据相连接对于准确的噪音建模至关重要.
- 了解喷气式噪声机制对于降低飞机噪声至关重要.
研究的目的:
- 用安装的GE-F404发动机的全尺度测量来实验验证经典喷气噪声理论.
- 为了确定GE-F404发动机在低和超音速条件下的声学效率.
- 将测量的声音功率变化与理论预测进行比较.
主要方法:
- 从安装的GE-F404发动机获取全尺寸声学数据.
- 在各种喷气速度下分析声音功率和声效.
- 实验结果与已建立的喷射噪声扩展规律进行比较.
主要成果:
- 测量的声音功率变化遵循了次音速喷气速度的第八次数定律.
- 在超音速喷气速度下,声音功率的变化与第三功率定律非常接近.
- 在超音速条件下,声学效率被确定为大约0.5-0.6%.
- 从次声速到超声速的整体声功率水平 (OAPWL) 的增加大于理论预测.
结论:
- 这项研究证实了经典喷气噪声理论在安装发动机中的次音速和超音速喷气速度的适用性.
- 实验数据支持分别为低音和超音速的第八级和第三级缩放规律.
- 在超音速时OAPWL增加的偏差表明了改进喷气噪声模型的潜在领域.
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