摘要
该文采用Fourier-Chebyshev谱方法,通过直接数值模拟研究了壁湍流拟序结构中低速条带的变化及相互作用。模拟了展向扰动作用下两条展向并列的直条带的失稳(抬升、振动、破碎)及其相互作用过程。结果表明,受基模式扰动的条带可以诱导流向涡的形成,而流向涡又促进条带的进一步抬升、振动和破碎。破碎后的条带在亚谐模式扰动作用下形成新的条带,新条带被再次诱导失稳。该文结果有助于研究壁湍流摩擦阻力的形成。
The evolution and interaction of low-speed streaks in wall-bounded turbulence are investigated by direct numerical simulation based on the standard Fourier-Chebyshev spectral method.The process of instability（including the lift-up,the oscillation and the breakdown）of two spanwise-aligned straight streaks and their interactions are simulated by imposing a spanwise disturbance.The results show that the streamwise vortices induced by the sinuous fundamental streaks can lead to the lift-up,the oscillation and the breakdown of streaks.The breakdown of streaks can lead to the regeneration of new sinuous streaks,and these new streaks are induced instable again due to the sinaous subharmonic mode.The results can help to study the formation of the skin-friction drag in the wall-bounded turbulence.
出处
《南京理工大学学报》
EI
CAS
CSCD
北大核心
2012年第2期278-284,共7页
Journal of Nanjing University of Science and Technology
基金
南京理工大学卓越计划创新团队项目
关键词
低速条带
不稳定性
相互作用
壁湍流
直接数值模拟
low-speed streaks
instability
interaction
wall-bounded turbulence
direct numerical simulation
