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Hi,

I am trying to use new key word 'SCHEME FOR ADVECTION OF K AND EPSILON' instead of 'TYPE OF ADVECTION'. But the model cannot run when SCHEME FOR ADVECTION OF K AND EPSILON = 3 or 4 or 5.

Error information shows that '200 SUB-ITERATIONS REQUIRED FOR THE DISTRIBUTION SCHEME. DECREASE THE TIME-STEP', but nothing works after decreasing of time step.

I don't understand why is it happened, Is there anybody could Help?

Best Regards,
Bin

Hello

For k-eps model, the advection part needs the most efficient scheme in a term of computation cost. That's why it is recommanded to use a fully implicit scheme like characteristics (scheme 1) or SUPG (option 2).
scheme 3, 4 and 5 are conditionnaly stable explicit schemes, that's why you have such kind of error. This means mainly that your time step is very big compared to the one admissible by the stability condition of the scheme.
In your case, it is preferable to change the scheme, or to reduce abruptly the time step or to change the turbulence model (use mixing length (scalar) or Spalart-Allmaras (1 equation)).

with my best regards

Riadh ATA