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安装的通用电气F404发动机的声功率水平光谱
Hunter J Pratt1, Logan T Mathews1, Tyce W Olaveson1
1Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USAhpratt7@byu.edu, lmathew3@byu.edu, to232@byu.edu, kentgee@bye.edu.
JASA express letters
|April 22, 2025
概括
军事喷气发动机噪声分析显示,飞行器类似的声音辐射正在转变,特别是在更高的推力设置下. 这项研究检查了F404发动机噪声在各种操作条件下.
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
- 喷气式推进系统 喷气式推进系统
背景情况:
- 了解军事喷气发动机噪声对于运营安全和环境影响评估至关重要.
- 之前的研究已经描述了喷气噪声,但在一系列操作条件下进行了详细的光谱分析.
研究的目的:
- 在安装在T-7A上的F404发动机上进行声功率频谱分析.
- 研究发动机运行条件,从中间推力到后燃机,如何影响声功率谱.
主要方法:
- 使用自由场压力光谱的表面积分计算了声功率水平光谱.
- 对半径为38米和76米的麦克风弧阵列进行了测量.
- 在计算中使用了轴对称辐射的假设.
主要成果:
- 频谱峰值频率区域 (大约100-500 Hz) 随着发动机条件的增加而扩大.
- 当与斯特鲁哈尔数绘制图时,随着发动机条件的加剧,光谱峰值下降.
- 与火箭噪声数据的比较表明,从军用喷气发动机发出的更多类似火箭的噪声辐射的趋势.
结论:
- 军用喷气发动机噪声特征随着操作条件的变化而演变,在后燃机设置时,向火箭式噪声显著转变.
- 这些发现表明,先进的军事喷气发动机可能与火箭推进系统有声辐射相似之处.
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