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What are rhoMin and rhoMax in rhoPimpleFoam?

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Old   January 9, 2013, 13:31
Default What are rhoMin and rhoMax in rhoPimpleFoam?
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in rhoPimpleFoam there are rhoMin and rhoMax what they mean?what are their coefficients?
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Old   January 11, 2013, 18:30
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The density in the solver rhoPimpleFoam is limited by the values "rhoMax" and "rhoMin" defined in fvSolutions.
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Old   January 12, 2013, 04:34
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thanks.how should it be adjusted based on case?
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Old   January 15, 2013, 12:43
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any idea about setting the rhoMin and rhoMax?
do we should a guess about minimum and maximum f rhos in the problem we solve?or its default should be used?
please give me a guide.
thanks alot.
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Old   January 15, 2013, 13:36
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These are values that you set based on your knowledge of the case you are simulating. It is up to you to ensure they are correct. If you look in the pEqn.H file you will see that is the operation done rho = max(rho,rhoMax) and the like.
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Old   January 16, 2013, 10:46
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im not sure about max and min of rho exactly.can i set it by a factor of safety?then turn the results less exact or just each iteration takes more time?
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Old   January 16, 2013, 13:55
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No, all that happens is that after the p is solved for, rho is then limited by the max/min values. All cells where rho is > rhoMax are set to rhoMax, all cells where rho < rhoMin are set to rhoMin.
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Old   January 16, 2013, 18:10
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excuse me.why it is intended?density is obtained from equation of state,isn't it?if thats true why rho is bounded?and if we acept that it doesn't seem an accurate way.could give me a bit guidance?
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Old   January 16, 2013, 18:21
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The bounding is there for your convenience; this is to bound the solution if you want. If you don't want rho to be bounded, just set rhoMin 0 and rhoMax to something absurdly high.
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