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RNG-LES model

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\mu _{eff}  = \mu \left[ {1 + H\left( x \right)} \right]^{1/3}
\mu _{eff}  = \mu \left[ {1 + H\left( x \right)} \right]^{1/3}
</math> . <br>
</math> . <br>
-
Where <math> H\left( x \right) </math> is given by: <br>
+
The function <math> H\left( x \right) </math> is defined as: <br>
:<math>
:<math>
Line 29: Line 29:
:<math>  
:<math>  
\mu _s  = \rho \left[ {C_{rng}} Vol^{1/3} \right]^{2} \begin{vmatrix} S \end{vmatrix}  
\mu _s  = \rho \left[ {C_{rng}} Vol^{1/3} \right]^{2} \begin{vmatrix} S \end{vmatrix}  
 +
</math>
 +
<br>
 +
Where <math> C_{rng}  </math> is given by <br>
 +
:<math>
 +
{C_{rng}  = 0.157}
</math>
</math>

Revision as of 08:23, 13 September 2005

Based on Renormalization Group Theory. Here  
\mu _{eff}  = \mu \left[ {1 + H\left( x \right)} \right]^{1/3}
.
The function  H\left( x \right) is defined as:


H\left( x \right)  
 \begin{matrix}
= x
 \begin{matrix}
 {} & ; & {x > 0}  \\ 
 \end{matrix} 
\\
= 0
 \begin{matrix}
  {} & ; & {x \le 0}  \\ 
 \end{matrix} 

 \end{matrix}


x is given by 
x = {{\mu _s \mu _{eff} } \over {\mu ^3 }} - C

Where  {C = 100} and \mu _s is given by:

 
\mu _s  = \rho \left[ {C_{rng}} Vol^{1/3} \right]^{2} \begin{vmatrix} S \end{vmatrix}


Where  C_{rng}  is given by

 
{C_{rng}  = 0.157}
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