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dt and smaller time step

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Old   May 30, 2013, 09:28
Default dt and smaller time step
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Jian Zhong
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Dear Foamers,

I am wondering how to use dt for some variables and another time steps smaller than dt for other variables.
Specifically,
dt :0.02 for V1......
and another dt (0.01, 20 increments of dt specified in the control) for other V2......

My best regards,
Jian
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Old   May 31, 2013, 03:20
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Anton Kidess
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Have a look at interFoam: Here we have an extra loop for subcycling of alpha, which means alpha will be solved with a fraction of the regular time step if activated.
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Old   May 31, 2013, 09:25
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Many thanks. But I am wondering how to activate the subcycling of total deltaT. Where can I find the 'pimple.dict()' and the corresponding tutorial case?
....
In the alphaEqnSubCycle.H,

label nAlphaCorr(readLabel(pimple.dict().lookup("nAlphaC orr")));

label nAlphaSubCycles(readLabel(pimple.dict().lookup("nA lphaSubCycles")));
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