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 decreasing turbulent instability near | + | 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 in near-wall simulations. |
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 08:02, 23 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 in near-wall simulations.
Another empiric profile that covers both the near wall and logarithmic region is the Reichardt profile.
