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Eddy length scale
Posted Aug 12, 2017, 10:40 a.m. EDT Computational Fluid Dynamics (CFD), Modeling Tools & Definitions, Parameters, Variables, & Functions, Results & Visualization, Studies & Solvers Version 5.1 0 Replies
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I was wondering if it's possible to apply the results from my turbulence model (k-ε) to calculate the different length scales of the generated eddies. The reason why I'm asking this is because I'm getting results that don't apply to the following rule:
L0> LEI > LDl
The value of LDl is always larger than my LEl.
Where:
L0= length scale of the largest eddy, k=turbulent kinetic energy, ε=dissipation rate, kinematic viscosity
LEl= demarcation line between energy (E) and inertial (I) ranges.
LDI = demarcation line between the dissipation (D) and inertial (I) ranges.
AND
n=(v^3/ε)^1/4;
L0= k^(3/2)/ε;
LEl=L0/6;
LDl=60*n
Are my assumptions correct or did I misunderstood something? Or is it because the k-ε model is not accurate in the region close to no-slip walls where k and ε exhibit large peaks.
Any help is much appreciated!
Hello Philippe Van Der Poel
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