Wall functions
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Revision as of 13:03, 13 June 2008 by Radi Sadek (Talk | contribs)
Based on law of the wall
A wall-function simulation normally requires that y plus of the first cell outside the walls is in the log-layer, which starts at about y plus 20 and, depending on the Re number, extends up to say y plus 200. In the log layer, there is equilibrium beteen production and dissipation of the turbulent kinetic energy, therefore dicreasing turbulent instability near to wall.
Another empiric profile that covers both the near wall and logarithmic region is the Reichardt profile.