Computational aeroacoustics: The low speed jet
Computational aeroacoustics: The low speed jet
复制标题
计算气动声学：低速喷射
作者：
E. Avital;Mikel Alonso;V. Supontisky
摘要本文对低速圆形、椭圆形和平面射流进行了基本的声学和流体力学计算研究。射流被假定为不可压缩的，并使用大涡模拟（LES）的方法进行了模拟。发出的声音是使用莱特希尔的声学类比计算的。两个配方使用，莱特希尔的应力张量配方和鲍威尔的涡声配方。为了考虑计算域的有限大小，对Powell公式提出了一种新的边界修正。模拟了中低雷诺数射流。与已知的流体动力学结果取得了良好的协议。这包括过渡过程的性质，例如，在椭圆射流和一些统计结果中的增强混合和轴切换。鲍威尔公式的新边界修正被证明是至关重要的，以实现良好的协议与莱特希尔的公式。在获得预期的渐近行为方面，至少对于圆形和椭圆形射流的高频预测取得了一些成功。两种公式都表明椭圆射流噪声级略低于圆形射流噪声级。在方向性和频谱方面与各种射流的已知结果取得了很好的一致性。
Abstract Low speed circular, elliptic and planar jets are investigated computationally for basic sound generation and hydrodynamics. The jets are assumed to be incompressible and are simulated using the large eddy simulation (LES) approach. The emitted sound is calculated using Lighthill’s acoustic analogy. Two formulations are used, Lighthill’s stress tensor formulation and Powell’s vortex sound formulation. A new boundary correction for Powell’s formulation is developed in order to account for the finite size of the computational domain. Low to moderate Reynolds number jets are simulated. Good agreement with known hydrodynamic results is achieved. This includes the nature of the transition process, e.g. enhanced mixing and axis switching in the elliptic jet and in some statistical results. The new boundary correction for Powell’s formulation proves to be vital in order to achieve good agreement with Lighthill’s formulation. Some success in high frequency prediction at least for the circular and elliptic jets is achieved in terms of getting the expected asymptotic behaviour. Both formulations show that the elliptic jet noise level is mildly lower than the circular jet noise level. Good to very good agreement is achieved in terms of directivities and frequency spectra with known results for the various jets.
低速平面射流的流体动力学和声音产生
DOI：
10.1115/1.2844581
发表时间：
2008
期刊：
Journal of Fluids Engineering
影响因子：
--
作者：
Suponitsky V
通讯作者：
Suponitsky V