摘要
本文采用频率分析法对Tollmien Schlichting波(T.-s.波)的共振干涉现象进行实验研究。结果表明,在不稳定的层流边界层的临界层附近测得的功率谱中,T.-s.波的能量集中在一个较窄的频段,其中有一至三个峰值分别对应于中性曲线内侧的T.-s.波的特征频率和最大增长率频率。T.-s.波的共振干涉将各特征分量的能量在它们的亚谐波分量通过中性曲线下支到达最大增长率点的相应R_8范围内传给它们的亚谐频,非特征频率的分量则迅速衰减,共振干涉的多次重复,使边界层逐步湍流化。
Resonant interaction phenomena of Tollmien-Schlichting waves (T. -S. waves) are examined experimentally by spectral analysis method. Results demonstrate that, in the spectra measured in the vicinity of the critical layer of the unstable boundary layer, the energy of T.-S. waves concentrates in a narrow band of frequency with one to three peaks in the power spectra, corresponding to the eigen-frequencies of T.-S. waves and the frequency with maximum growth rate located between the upper and lower branches of the neutral cruve. The resonant interactions transfer the energy of these eigencomponents to their subsequent subharmonics in ?range of R8* where their growth rates increase from zero to a maximum value, and the boundary layer becomes turbulent after the third resonant interaction.
出处
《力学学报》
EI
CSCD
北大核心
1989年第2期140-144,共5页
Chinese Journal of Theoretical and Applied Mechanics
关键词
平板
边界层
T-S波
共振
干涉
resonant interaction, subharmonic frequency, exitation frequency, amplitude distribution, growth rate
