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预测加热超音速喷射器 (包括火箭) 的总体声力和最大总体声压水平的方法
1Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.
The Journal of the Acoustical Society of America
|July 14, 2025
概括
新的模型预测了加热超音速喷气式飞机和火箭的声音水平. 这项研究提供了简单的方法,可以很准确地估计总体声功率水平 (OAPWL) 和最大总体声压水平 (OASPLmax).
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:
- 之前的研究建立了用于估计喷气式发动机和火箭发动机的声功率和压力水平的模型.
- 现有的模型提供了基于基本发动机参数预测声学排放的基础.
研究的目的:
- 开发和介绍基于物理的简单方法,用于预测加热超音速喷气式飞机和火箭的总体声功率水平 (OAPWL) 和最大总体声压水平 (OASPLmax).
- 引入一种方法来计算对OASPLmax的地面影响.
- 通过使用火箭发射和喷气发动机操作的真实数据来验证预测模型.
主要方法:
- 利用加热超音速喷射器和火箭的基本流动特性来导出预测方程.
- 开发了一种特定的模型,将地面反射效应纳入声压水平.
- 收集和分析了来自Atlas V和Vulcan Centaur火箭发射的声学数据.
- 收集了F404喷气发动机在各种推力设置 (38%到后燃机) 的运行数据.
主要成果:
- 开发的方法为加热超音速喷气式飞机和火箭中的OASPLmax提供了准确的预测.
- 模型性能评估显示,在火箭和喷气式发动机条件下,与测量数据保持良好一致.
- 对于OASPLmax预测的根平均平方误差在评估的场景中小于2dB.
结论:
- 提出的简单方法有效地预测OAPWL和OASPLmax用于加热的超音速喷气式飞机和火箭.
- 这些模型表现出良好的预测能力,与运营火箭和喷气发动机数据进行验证.
- 包括地面效应估计在内增强了OASPLmax预测的实际适用性.
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