Chini G P, Montemuro B, White C M, Klewicki J
Integrated Applied Mathematics Program, University of New Hampshire, Durham, NH 03824, USA
Department of Mechanical Engineering, University of New Hampshire, Durham, NH 03824, USA.
Philos Trans A Math Phys Eng Sci. 2017 Mar 13;375(2089). doi: 10.1098/rsta.2016.0090.
Field observations and laboratory experiments suggest that at high Reynolds numbers Re the outer region of turbulent boundary layers self-organizes into quasi-uniform momentum zones (UMZs) separated by internal shear layers termed 'vortical fissures' (VFs). Motivated by this emergent structure, a conceptual model is proposed with dynamical components that collectively have the potential to generate a self-sustaining interaction between a single VF and adjacent UMZs. A large-Re asymptotic analysis of the governing incompressible Navier-Stokes equation is performed to derive reduced equation sets for the streamwise-averaged and streamwise-fluctuating flow within the VF and UMZs. The simplified equations reveal the dominant physics within-and isolate possible coupling mechanisms among-these different regions of the flow.This article is part of the themed issue 'Toward the development of high-fidelity models of wall turbulence at large Reynolds number'.
现场观测和实验室实验表明，在高雷诺数Re下，湍流边界层的外部区域会自组织成准均匀动量区（UMZs），这些区域由被称为“涡旋裂缝”（VFs）的内部剪切层分隔。受这种涌现结构的启发，提出了一个概念模型，其动力学组件共同具有在单个VF和相邻UMZs之间产生自持相互作用的潜力。对不可压缩Navier-Stokes控制方程进行大Re渐近分析，以推导VF和UMZs内流向平均流和流向脉动流的简化方程组。简化后的方程揭示了流动中这些不同区域内的主导物理现象，并分离出了可能的耦合机制。本文是主题为“迈向大雷诺数下壁面湍流高保真模型的发展”这一特刊的一部分。
