Interaction between a large-scale structure and near-wall structures in channel flow
Interaction between a large-scale structure and near-wall structures in channel flow
复制标题
DOI：
10.1017/s002211200400237x
复制
发表时间：
2005-02
影响因子：
3.7
通讯作者：
S. Toh;T. Itano
中科院分区：
文献类型：
--
作者：
S. Toh;T. Itano
在雷诺数为137和349时，对展向范围相对较宽但流向长度最小的周期区域内的槽道湍流进行了直接数值模拟。大规模的结构，以前观察到的研究中使用巨大的计算域的湍流槽道流动也存在，即使在本研究的流向最小的渠道。此外，域的流向长度的限制，强制执行大型结构和近壁结构之间的相互作用，从而使得它易于提取一个简单的循环的过程中维持的结构，在目前的渠道流。结果表明，大规模的结构产生的集体行为的近壁结构，后者的产生反过来又增强了大规模的结构。因此，近壁和大型结构在共同支撑循环中相互作用。
Direct numerical simulation of a turbulent channel flow in a periodic domain of relatively wide spanwise extent, but minimal streamwise length, is carried out at Reynolds numbers $\Rey_\tau\,{=}\,137$ and 349. The large-scale structures previously observed in studies of turbulent channel flow using huge computational domains are also shown to exist even in the streamwise-minimal channels of the present study. Moreover, the limitation of the streamwise length of the domain enforces the interaction between large-scale structures and near-wall structures, which consequently makes it tractable to extract a simple cycle of processes sustaining the structures in the present channel flow. It is shown that the large-scale structures are generated by the collective behaviour of near-wall structures and that the generation of the latter is in turn enhanced by the large-scale structures. Hence, near-wall and large-scale structures interact in a co-supporting cycle.