Guidelines for Modeling a 2D Rough Wall Channel Flow
Guidelines for Modeling a 2D Rough Wall Channel Flow
复制标题
二维粗糙壁通道流建模指南
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
R. Antonia
中科院分区：
文献类型：
--
作者：
S. Leonardi;P. Orlandi;L. Djenidi;R. Antonia
利用直接数值模拟（DNSs）得到的数据，研究了二维粗糙元对槽道湍流雷诺应力各向异性张量B {ij}$和能量耗散率各向异性张量d {ij}$的影响。粗糙度单元由尺寸为$k$的横向方形杆组成，仅放置在通道的一个壁上。当$k$保持不变时（$k/h = 0.1$，$h$是通道的半宽），棒之间的间距$w$从$w/k = 1$变化到$w/k = 59$。结果表明，w/k的变化可以显著地改变壁面区域的流动结构。近壁区域的建模需要反映由$w/k$的变化引起的结构变化。在雷诺应力预算的基础上，需要注意湍流能量和压力扩散项，而局部各向同性可能是能量耗散率的合理近似值，特别是在阻力接近其最大值的w/k范围内。
The effects of 2-D roughness elements on the Reynolds stress anisotropy tensor, $b_{ij}$ and of the energy dissipation rate anisotropy tensor $d_{ij}$ of a turbulent channel flow are investigated using data obtained from direct numerical simulations (DNSs). The roughness elements consist of transverse square rods of size $k$, placed on one wall of the channel only. While $k$ is kept constant ($k/h = 0.1$, $h$ is the half-width of the channel), the spacing $w$ between the rods is varied from $w/k = 1$ to $w/k = 59$. The results show that the variation in $w/k$ can dramatically change the structure of the wall region flow. The modeling of the near-wall region needs to reflect the structural changes caused by the variation in $w/k$. On the basis of the Reynolds stress budgets, attention needs to be given to the turbulent energy and pressure diffusion terms while local isotropy may be a reasonable approximation for the energy dissipation rate, especially over a range of $w/k$ for which the drag is near its maximum.