Exact Eddy-Viscosity Equation for Turbulent Wall Flows—Implications for Computational Fluid Dynamics Models
نویسندگان
چکیده
For turbulent channel flow, pipe and zero-pressure gradient boundary layer, Heinz yielded recently analytical formulas for the eddy viscosity as a product of function (the wall-normal distance scaled in inner units) same outer units). By calculating eddy-viscosity diffusion term, an exact high-Reynolds-number equation with one production two dissipation terms is constructed those flows. One term universal, peaks near wall, scales mainly . The second, smaller one, flow dependent, wake, between, similarly. universal implies length scale analogous to von Karman used scale-adaptive simulation models Menter. This also appears term. confirms relevance these scales. An asymptotic analysis all budget limit infinite Reynolds numbers provided. yields test bench existing Reynolds-averaged Navier–Stokes similar equation. It shown that some models, e.g., Spalart Allmaras, do not respect physics: they display peak near-wall region. most promising model, modified. As step forward toward solution wall damping problem, our model behaves much more correctly
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ژورنال
عنوان ژورنال: AIAA Journal
سال: 2022
ISSN: ['0001-1452', '1533-385X', '1081-0102']
DOI: https://doi.org/10.2514/1.j060761