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pablodecastillo April 25, 2012 05:50

interFoam and alphaEqn.H

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


Phicau April 25, 2012 06:55


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.


santiagomarquezd May 1, 2012 09:52

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.


pablodecastillo May 7, 2012 14:57

But looking for steady state loss or gain mass is not going to be relevant or yes?


santiagomarquezd May 8, 2012 13:59

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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