Wall functions
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Based on [[Law of the wall|law of the wall]] | Based on [[Law of the wall|law of the wall]] | ||
| - | A wall-function simulation normally requires that [[Dimensionless wall distance|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 between production and dissipation of the turbulent kinetic energy, therefore | + | A wall-function simulation normally requires that [[Dimensionless wall distance|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 between production and dissipation of the turbulent kinetic energy, therefore decreasing turbulent instability near to wall. |
Another empiric profile that covers both the near wall and logarithmic region is the [[Reichardt profile|Reichardt profile]]. | Another empiric profile that covers both the near wall and logarithmic region is the [[Reichardt profile|Reichardt profile]]. | ||
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Revision as of 08:21, 16 June 2008
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 between production and dissipation of the turbulent kinetic energy, therefore decreasing turbulent instability near to wall.
Another empiric profile that covers both the near wall and logarithmic region is the Reichardt profile.
