摘要
对均匀各向同性湍流的频率波数能量谱进行了初步研究,得出均匀各向同性湍流中能量随时间、空间尺度分布的解析表达式,并运用直接数值模拟的方法对理论预测进行验证.数值结果很好地支持了理论预测:横扫速度是决定频率波数能量谱的特征量.
The energy spectra with respect to wavenumbers in isotropic homogeneous turbulence have been studied thoroughly. However, less attention has been paid to the frequency-wavenumber energy spectra, which are important to the temporal statistics in turbulence and aeroacoustics. In this paper, the frequency-wavenumber energy spectra are at first formulated based on the Kolmogorov's classic theory and the sweeping hypothesis. A direct numerical simulation on isotropic turbulence is carried out to verify our theoretical predictions. It is indicated from our theoretical arguments and numerical simulations that the sweeping velocity dominates the frequency-wavenumber energy spectra. The frequency energy spectra at different wavenumbers are shown to be collapsed under the normalization of the sweeping velocity.
出处
《力学学报》
EI
CSCD
北大核心
2003年第3期317-320,共4页
Chinese Journal of Theoretical and Applied Mechanics
关键词
均匀各向同性湍流
频率波数能量谱
时间关联函数
横扫假设
直接数值模拟
isotropic turbulence, time correlation, frequency-wavenumber energy spectra, sweeping hypothesis, direct numerical simulation
