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Regarding unbounded alpha values -interFoam |
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July 31, 2017, 07:13 |
Regarding unbounded alpha values -interFoam
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#1 |
Member
Phanindra
Join Date: Jan 2013
Posts: 39
Rep Power: 13 |
Dear Foamers,
I'm using interFoam for flow over flat plate. Over the course of time I see the alpha values increasing beyond 1. With refined mesh , with all schemes including upwind. . Can anyone of you help me to overcome this issue I'm attaching fvschemes,fvsolution and p_rgh files for your perusal.fvSchemes.txt fvSolution.txt p_rgh.txt |
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July 31, 2017, 07:56 |
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#2 |
Senior Member
Kevin van As
Join Date: Sep 2014
Location: TU Delft, The Netherlands
Posts: 252
Rep Power: 20 |
You can use a limited scheme as convective scheme for the alpha equation, for example:
Code:
div(phi,alpha) Gauss limitedVanLeer 0 1; //vanLeer; div(phirb,alpha) Gauss limitedLinear 0 1; //linear; |
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August 25, 2017, 20:29 |
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#3 |
Senior Member
Santiago Marquez Damian
Join Date: Aug 2009
Location: Santa Fe, Santa Fe, Argentina
Posts: 452
Rep Power: 24 |
Hello, the MULES integrator mostly overrides the fluxes computed by the limiters, therefore the whole thing is related to MULES. Try to reduce your time-step or using more nAlphaSubCycles.
Regards.
__________________
Santiago MÁRQUEZ DAMIÁN, Ph.D. Research Scientist Research Center for Computational Methods (CIMEC) - CONICET/UNL Tel: 54-342-4511594 Int. 7032 Colectora Ruta Nac. 168 / Paraje El Pozo (3000) Santa Fe - Argentina. http://www.cimec.org.ar |
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July 5, 2018, 04:32 |
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#4 | |
Senior Member
Elham
Join Date: Oct 2009
Posts: 184
Rep Power: 16 |
Quote:
As my alpha was unbounded I used the following expression. Code:
alpha1=max(scalar(0.0),min(alpha1,scalar(1.0))); Cheers, Elham |
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March 6, 2019, 08:05 |
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#5 |
Member
Mahmoud Aboukhedr
Join Date: Feb 2014
Location: London
Posts: 40
Rep Power: 12 |
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March 6, 2019, 09:06 |
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#6 |
Senior Member
Santiago Marquez Damian
Join Date: Aug 2009
Location: Santa Fe, Santa Fe, Argentina
Posts: 452
Rep Power: 24 |
Hello, that method is non-conservative and should be avoided.
Regards
__________________
Santiago MÁRQUEZ DAMIÁN, Ph.D. Research Scientist Research Center for Computational Methods (CIMEC) - CONICET/UNL Tel: 54-342-4511594 Int. 7032 Colectora Ruta Nac. 168 / Paraje El Pozo (3000) Santa Fe - Argentina. http://www.cimec.org.ar |
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March 6, 2019, 09:34 |
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#7 | |
Member
Mahmoud Aboukhedr
Join Date: Feb 2014
Location: London
Posts: 40
Rep Power: 12 |
Quote:
Currently, I see an increase in my alpha value due to the unbounded alpha max and min |
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May 14, 2020, 11:10 |
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#8 |
New Member
Liz
Join Date: Apr 2020
Location: Germany
Posts: 10
Rep Power: 6 |
Hi Mahmoud, did you solve this problem? I'm saving the same problem right now with my simulation.
Regards |
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September 25, 2021, 06:05 |
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#9 |
New Member
Hamid
Join Date: Mar 2012
Posts: 20
Rep Power: 14 |
It may be a little late to give an answer here, but have you tried isoAdvectors i.e., interIsoFoam? It gives bounded alpha.water fields
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