近壁湍流相干结构演化机理的研究

从流动稳定性理论中的共振三波出发，提出了近壁湍流相干结构的理论模型，采用紧致有限差分和Ｆｏｕｒｉｅｒ谱展开相结合的方法对近壁湍流相干地数值模拟。结果表明，在小初始幅值下，单个相干结构不容易被激发，仅在相当大的初始幅值下，它可能被激发增长起来。该结论与文献「１」的结果吻合，另外，非对称单个相干结构对比对称单个相干结构更容易增长。

The Study of the Evolutive Mechanism of the Coherent Structure in the Wall Region of a Turbulent Flow

This paper aims to investigate the coherent structure in the wall region of a turbulent flow by the numerical simulation combining compact finite differences and Fourier spectral expansion. The theoretical model of the coherent structures in the wall region of a turbulent flow is proposed, using the idea of resonant triad of the theory of hydrodynamic stability. The results have showed that a single coherent structure is not easily stimulated in a small initial amplitude, and only in a quite large initial amplitude is easily stimulated and is quickly amplified. The results compare reasonally well with those in 1]. Compared with the single coherent structure of symmetry, the one of unsymmtry grows much more easily.