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What is the meaning of min(alpha)

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Old   August 14, 2013, 23:22
Default What is the meaning of min(alpha)
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Kshitij kunte
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Hi All,

I'm using interFoam solver in openFoam and the alpha(min) is becoming negative. What is the meaning of the value (mean averaged, or the minimum value of alpha in all the cells). Can any one please help me.

Thanks,
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Old   August 15, 2013, 08:00
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Mohsen KiaMansouri
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Try to bound Alpha between 0 and 1 by using limited schemes in fvSchemes. e.g:
Code:
div(phi,alpha1) Gauss vanLeer01;             //HTRL to bound the vanLeer scheme strictly between 0 and 1 to avoid negative and higher than 1 alpha
see also section 4.4.1.1 Schemes for strictly bounded scalar fields of the User-Guide for more info
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Old   August 15, 2013, 08:11
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Kshitij kunte
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Hi,

Thanks for the suggestion, actually I'm simulating diesel flow atomization inside injector atomization. For this kind of approach to handle the advective term they are using NVD(Normalized Variable Diagram) based schemes, like gamma and SFCD. The moment I implement these schemes my volume fraction becomes negative.
Currently I'm using the upwind scheme to keep the alpha bounded.
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