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Old   August 29, 2002, 03:33
Default backflow volume fraction
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fei
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I use the multiphase model,in the pressure outlet boundary condition,there is a "backflow volume fraction",i don't understand what's these means,maybe you can help me.Thanks for your help!!!
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Old   September 1, 2002, 10:47
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sri
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the backflow vof is used only when there is a reverse flow at the outlet.your convergence would be faster if you give a reasonable value.
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Old   September 1, 2002, 20:09
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fei
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thank you very much!another thing is how can get the backflow vof,may through the experiment?
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Old   September 2, 2002, 03:40
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this value has to be intutively.when reverse flow is expected in your domain,then the value has to come from experiments
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Old   September 2, 2002, 18:44
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your help is very useful,thank you very much.
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Old   February 19, 2011, 07:29
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Hi,
how can i set outlet volume fraction when set pressure outlet?
is it related to backflow?
regards.
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Old   February 19, 2011, 12:53
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In regards to this.. could the backflow volume fraction be used to restrict the seondary phase from leaving the system at a pressure outlet?
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Old   February 19, 2011, 14:32
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Thanks,
So you mean if back flow volume fraction set to 1 only that phase can exit from that patch? What's your idea about above comments about backflow?
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