A Weak-Scattering Model for Turbine-Tone Haystacking outside the Cone of Silence
A Weak-Scattering Model for Turbine-Tone Haystacking outside the Cone of Silence
复制标题
沉默锥外涡轮音干草堆的弱散射模型
DOI：
10.1260/1475-472x.10.1.17
复制
发表时间：
2010
影响因子：
1
通讯作者：
A. McAlpine
中科院分区：
文献类型：
--
作者：
C. Powles;B. Tester;A. McAlpine
本文研究射流剪切层中湍流对声的散射。流中的湍流、随时间变化的不均匀性以这样的方式散射音调声场，使得频谱变宽，这降低了入射音调的水平，但增加了音调频率周围的宽带水平。的散射过程模拟观察员以外的沉默锥的射流，使用高频渐近方法和弱散射假设。导出了散射场远场功率谱密度的解析模型，并将计算结果与实验数据进行了比较。该模型正确地预测了作为喷射速度和音调频率的函数的散射场的行为。
We consider the scattering of sound by turbulence in a jet shear layer. The turbulent, time-varying inhomogeneities in the flow scatter tonal sound fields in such a way as to give spectral broadening, which decreases the level of the incident tone, but increases the broadband level around the frequency of the tone. The scattering process is modelled for observers outside the cone of silence of the jet, using high-frequency asymptotic methods and a weak-scattering assumption. An analytical model for the far-field power spectral density of the scattered field is derived, and the result is compared to experimental data. The model correctly predicts the behaviour of the scattered field as a function of jet velocity and tone frequency.