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-   -   adaptative time step algorithm (http://www.cfd-online.com/Forums/openfoam-programming-development/120872-adaptative-time-step-algorithm.html)

Jacks July 16, 2013 13:33

adaptative time step algorithm
 
Hi everyone,

Does anyone know from which source or why is the adapatative time step implemented in such way in setDeltaT.H source file :

Code:

scalar maxDeltaTFact = maxCo/(CoNum + SMALL);
scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact),1.2); 

runTime.setDeltaT (
      min (
                deltaTFact*runTime.deltaTValue(),
                maxDeltaT )
  );

Thanks,

Jacks

andyru July 17, 2013 14:41

It scales the deltaT if courant number is to high "directly", but increases deltaT very slowly.

I think, you can also change the factor 1.2. I think, it is an assumption.

Hope, this helps.


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