使用计算流体动力学预测旋转器尾端噪声的方法
Jordon Won1, Nikos Trembois1, Seongkyu Lee1
1Mechanical and Aerospace Engineering, University of California, Davis, California 95616, USA.
The Journal of the Acoustical Society of America
|August 29, 2025
概括
预测转子流边界层噪声至关重要. 从截面力推导边界层参数提供了最可靠的计算流体动力学 (CFD) 预测,通过实验数据验证.
科学领域:
- 航空航天工程
- 听力学
- 计算流体动力学
背景情况:
- 旋翼飞机噪声,特别是流边界层尾端噪声,是航空航天应用中的一个重要问题.
- 这种噪声的准确预测需要经验模型的可靠输入,例如边界层参数.
- 计算流体动力学 (CFD) 是模拟空气动力学现象的强大工具,但其直接用于噪声预测需要仔细的参数提取.
研究的目的:
- 调查和比较三种不同的方法来获得边界层参数,这些参数对于预测旋转器流边界层尾端噪声至关重要.
- 评估计算流体动力学 (CFD) 与Amiet的尾端噪声模型用于噪声预测的有效性.
- 确定从CFD数据中推导边界层参数的最可靠和最有效的方法.
主要方法:
- 为了提取边界层参数,开发了三种方法:直接从3D CFD解决方案中提取,从截面力中推导,并从压力系数分布中确定.
- 这些参数被用作实证墙壁压力谱模型的输入.
- 艾美特的尾端噪声模型与CFD模拟一起使用.
主要成果:
- 从截面正常和弦力中推导边界层参数的方法被证明是最可靠和最有效的.
- 使用这种方法的预测显示,在两种转子配置的各种操作条件下,与实验数据有很好的一致性.
- 尾端噪声对有效攻击角度的变化敏感度很低,但对气翼选择,叶片几何和旋转速度敏感度很高.
结论:
- 从截面力得出边界层参数是使用CFD预测旋转器尾端噪声的可靠方法.
- 这项研究强调了旋翼设计参数 (气翼,叶片几何,速度) 对噪声水平的关键影响.
- 与经验模型相结合的CFD为了解和减轻旋转器噪声提供了可行的框架.
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