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DES Length Scale,grid spacing,delta max

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Old   January 27, 2014, 08:11
Default DES Length Scale,grid spacing,delta max
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Ali.E
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Hello all,
I want to compute delta x (distance between two cell points) in a 3D simulation. Actually, I want to caclucate DES Length Scale and maximum grid spacing is a important parameter to calculate. Actually, 3 grid spacing is needet to calculate in 3D problem and the maximum of them is used in DES Length Scale calculation. My problem is how can I find the grid spacing for each cells. Please help me
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Old   February 5, 2014, 15:29
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I think that the best way is writting a udf which computes the length scale.
the length scal equation is:

L_s=sqrt(k)/(Bs*delta_max*C_des*w)
Bs=0.09 , C_des=0.61
k=turbulent kinitic energy
w=specific dissipation rate
delta_max=max(delta_x,delta_y,delta_z)

may I ask you which macros should be used?
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