Computation of turbulence-generated noise by large-eddy simulation


Autoria(s): 姚华栋; 何国威; 张星
Data(s)

2007

Resumo

The hybrid method of large eddy simulation (LES) and the Lighthill analogy is being developed to compute the sound radiated from turbulent flows. The results obtained from the hybrid method are often contaminated by the absence of small scales in LES, since the energy level of sound is much smaller than that of turbulent flows. Previous researches investigate the effects of subgrid sacle (SGS) eddies on the frequency spectra of sound radiated by isotropic turbulence and suggest a SGS noise model to represent the SGS contributions to the frequency spectra. Their investigations are conducted in physical space and are unavoidably influenced by boundary conditions. In this paper, we propose to perform such calculations in Fourier space so that the effects of boundary conditions can be correctly treated. Posteriori tests are carried out to investigate the SGS contribution to the sound. The results obtained recover the -7/2 law within certain wave-number ranges, but under-estimate the amplitudes of the frequency spectra. The reason for the underestimation is also discussed.

Identificador

http://dspace.imech.ac.cn/handle/311007/25446

http://www.irgrid.ac.cn/handle/1471x/6829

Idioma(s)

英语

Publicador

Beijing

Fonte

New Trends In Fluid Mechanics Research - Proceedings Of The Fifth International Conference On Fluid Mechanics . 5th International Conference on Fluid Mechanics, Shanghai, PEOPLES R CHINA. AUG 15-19, 2007, pp.83-86.

Palavras-Chave #Sound Radiation #Isotropic Turbulence #Large Eddy Simulation #Lighthill Analogy #Isotropic Turbulence #Radiated Noise #Sound
Tipo

会议论文