THE RADIATED NOISE FROM ISOTROPIC TURBULENCE WITH APPLICATIONS TO THE THEORY OF JET NOISE
THE RADIATED NOISE FROM ISOTROPIC TURBULENCE WITH APPLICATIONS TO THE THEORY OF JET NOISE
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DOI：
10.1006/jsvi.1996.0074
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发表时间：
1996-02
影响因子：
4.7
通讯作者：
G. Lilley
中科院分区：
文献类型：
--
作者：
G. Lilley
摘要Lighthill[1]在他的空气动力噪声理论中，考虑了可压缩非定常流动的拟有限但无界区域的噪声。Proudman[2]首次将该理论应用于低马赫数和高雷诺数的各向同性湍流情况。最近，Lilley[3]和Sarkar and Hussaini[4]利用直接数值模拟(DNS)重新考虑了这个问题，并首次评估了四阶空间延迟时间协方差，这是Lighthill确定声辐射声功率理论的核心。在这篇文章中，以前的工作被扩展到包括运动中的热流体在静止时浸入外部介质中的影响。在引入一个简单的假设的基础上，将这些关于各向同性湍流辐射噪声的结果用于预测气体热湍流射流辐射的噪声功率。计算结果与亚音速和超音速热喷流的远场实验数据定性一致，前提是热喷流完全膨胀且没有激波。该理论起源于20世纪50年代莱特希尔的空气动力学噪声理论发表后，当时E·J·理查兹教授和他们的同事正在努力预测喷气发动机的噪声，并在不影响性能的情况下建立降低噪声的方法。
Abstract Lighthill [1], in his Theory of Aerodynamic Noise , considered the noise from a pseudo-finite yet unbounded domain of compressible unsteady flow. The first application of this theory was given by Proudman [2] for the case of isotropic turbulence at low Mach numbers and high Reynolds numbers. More recently, Lilley [3] and Sarkar and Hussaini [4], using Direct Numerical Simulation (DNS), have reconsidered this problem, and evaluated for the first time the fourth order space-retarded time covariance which is central to Lighthill's theory for the determination of the acoustic radiated sound power. In this paper the previous work is extended to include the effects of a hot fluid in motion immersed in an external medium at rest. On the introduction of a simple hypothesis these results for the noise radiated from isotropic turbulence are used to predict the noise power radiated from a gaseous hot turbulent jet. The results are found to be qualitatively in agreement with far field experimental data on hot jets at subsonic and supersonic speeds, provided the jets are fully expanded and are devoid of shock waves. The theory has its origins in the 1950s following the publication of Lighthill's theory of aerodynamic noise, when Professor E. J. Richards, the author and their colleagues were striving to predict the noise from jet engines and establish methods for their noise reduction, without loss in performance.