通过冷却器横流中的热排气喷气进行平稳状态声音传播:一项计算研究
O Leav1, B Cazzolato1, C Howard1
1School of Mechanical Engineering, University of Adelaide, Adelaide, Australia.
The Journal of the Acoustical Society of America
|July 13, 2023
概括
交叉流中的加热喷气体发出的声音辐射是复杂的. 流梯度显著改变声道,导致下游噪声水平高于简单模型预测的水平.
科学领域:
- 声学 声学 在声学方面
- 流体动力学 流体动力学
- 计算科学 计算科学
背景情况:
- 工业废气系统通常涉及冷却横流中的加热喷气.
- 在这样的条件下了解声音辐射对于降低噪声至关重要.
研究的目的:
- 为了研究从冷却器交叉流中加热喷射器发出的声辐射.
- 分析流体声学相互作用并解释下游声音水平的升高.
主要方法:
- 混合模型结合了稳态计算流体动力学 (CFD) 和计算声学.
- 对于流量和温度领域,CFD使用雷诺斯平均纳维埃-斯托克斯方程.
- 线性声波方程与适用于声音传播的平均流量.
主要成果:
- 流量显著改变了声音传播路径.
- 下游的声音水平超过了声学断模型的预测.
- 由于温度和速度梯度的折射是声音传播的主要机制.
结论:
- 声音传播对离管道出口的近距离,波数,温度和速度比非常敏感.
- 该研究解释了复杂的辐射模式,导致下游噪声高于预期.
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