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Old   March 27, 2013, 05:27
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Tobias Holzmann
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Hi all,

I am working with interFoam over an year and try to use the LTS now.

For that I do not know what these options are and used for:

Code:
    nAlphaSweepIter 1;

    rDeltaTSmoothingCoeff 0.1;
    rDeltaTDampingCoeff 1;
    maxDeltaT       0.8
Can someone tell me how I can interprete that coefficients?
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Old   March 27, 2013, 08:42
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LTS uses a method that "assign at each cell a local time" so you can have a pseudo time advancement not constrined by the cfl condition in the smaller cell.

but you either don't want huge differences of time across neighboring cells, so the dampening coeff prevents oscillations in a checkboarding manner and the smoothing is to avoid spikes and have the local timestep as "smooth" as possible across nearby cells.
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Old   March 29, 2013, 11:28
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Quote:
Originally Posted by sail View Post
LTS uses a method that "assign at each cell a local time" so you can have a pseudo time advancement not constrined by the cfl condition in the smaller cell.

but you either don't want huge differences of time across neighboring cells, so the dampening coeff prevents oscillations in a checkboarding manner and the smoothing is to avoid spikes and have the local timestep as "smooth" as possible across nearby cells.
Hi,

thanks for your replay.

So the two coefficents helps to stabilize the numeric
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