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Fixed Outlet Mass Flux boundary condition?

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Old   June 30, 2010, 03:52
Default Fixed Outlet Mass Flux boundary condition?
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Hi!

I read somewhere that Outlet Mass Flux boundary conditions are being discussed in this form... but i did many searches and couldnt find anything.

Basically my question is

Is it possible to set the mass flux at the outlet? If so, what boundary condtions do i have to call??

ie. type FixedOutletMassFlux: ?? (does this exist)

Thanks in advance Foamers!

Cheers,
T
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Old   June 30, 2010, 07:37
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Stefan Herbert
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Hello,

try flowRateInletVelocity with a negative flowRate. I have never used it this way, but it should work though.

Regards,
Stefan
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Old   June 30, 2010, 21:44
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Hi Herbert,

I have indeed tried flowRateVelocityInlet but to no success. Any other options. I am unclear as to why its not working, but it seems that when the inlet velocity goes from positive to negative, the flow direction is still the same... which completely does not makesense to me! and then when it hits 0, a whole pile of errors come up. And as we all know, debugging openFoam errors are next to impossible.

Is it possible to just set the outlet velocity whilst leaving the inlet velocity as an $internalField? I have tried setting outlet velocity but it doesnt seem to work. Is there a different boundary condition that I should be using?

Cheers,
T

Last edited by trex930; July 1, 2010 at 02:39.
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