槽道湍流近壁区相干结构的数值模拟

NUMERICAL STUDY OF THE CONERENT STKUCTURES IN WALL REGION OF A CHANNEL FLOW

从流动稳定性理论中的共振三波出发，采用类似湍流直接数值模拟中的最小单元概念，用伪谱方法，对槽道湍流近壁区的单个相干结构进行了数值模拟，得到了与实验基本一致的结果，同时也搞清楚了在谱方法中用Ｃｈｅｂｙｓｈｅｖ－τ方法和配置点法哪个更精确的问题。

This paper aims to investigate the single coherent structure in the wall regionof a channel fiow by minimal flow unit of direct numerical simulation using psendospectralmethod. The mechanism for the formation and evolution of the coherent structure wasstudied by using the idea of resonant triad of the theory of hydrodynamic stability Theresults compared reasonally well with experirnental observations。Meanwhile,it is foundthat collocation method has higher precision than Chebyshev-τmethod。