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Old   April 25, 2012, 05:50
Default interFoam and alphaEqn.H
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Hello,

Why in alphaEqn.H is it not added alpha1 = max(min(alpha1, scalar(1)), scalar(0)); i mean this artificial bounded?

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Old   April 25, 2012, 06:55
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Hi

MULES solver ensures boundedness, that is why the last 2 inputs are 0 and 1, the bounds of alpha1. This is achieved by the use of limiters.

The final result may show values greater than 1 or lower than 0, but with differences of the order of 10^-5, which is negligible.

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Old   May 1, 2012, 09:52
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Using an artificial bounding of this kinds leads to a non-phase-preserving algorithm due it 'cuts' with having in account the conservative properties of the alpha equation. In other words you will lose or gain mass.

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Old   May 7, 2012, 14:57
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But looking for steady state loss or gain mass is not going to be relevant or yes?

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Old   May 8, 2012, 13:59
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Hhmm, I don't know, but since the solver is unsteady probably it will blow up before reach the steady state due mass preservation problems.

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