No CFD / MECHA - 24 - 2012 DATE : November 15 , 2012 TITLE Exploring k and ǫ with Modified Spalart – Allmaras One – Equation Model
نویسنده
چکیده
A wall–distance–free version of the Spalart–Allmaras (SA) one–equation model is proposed to account for the distinct effects of low-Reynolds number (LRN) and wall proximity. The turbulent kinetic energy k and the dissipation rate ǫ are evaluated using the ν̃t–transport equation together with some empirical relations. The model coefficients/functions preserve the anisotropic characteristics of turbulence in the sense that they are sensitized to rotational and nonequilibrium flows. The model is validated against a few well-documented flow cases, yielding predictions in good agreement with the direct numerical simulation (DNS) and experimental data. Comparisons indicate that the present model offers some improvement over the Spalart–Allmaras one– equation model and competitiveness with the SST k–ω model.
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