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Outlet conditions in BuoyantFoam

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Old   October 13, 2007, 13:58
Default Hi, having some problems w
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Jon Tegner
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having some problems with outlet-conditions in a BuoyantFoam simulation. Case is basically the same as the hotRoom tutorial case, BUT with an inlet and an outlet with given pressure both at inlet and outlet (and hence producing a "chimney" effect). On the inlet pressureInlet is used, and on the outlet pressureOutlet. The last means that a fixed value is used for the pressure at the outlet, but for all other variables zeroGradient is used. This seems to work fine in most cases, but in some situations a very small "backflow" develops at the outlet, and as soon as this happens the solution becomes unstable (starting with the temperature). Are there other, "better suited", boundary conditions I can use in this situation?
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Old   October 15, 2007, 04:27
Default Check out the inletOutlet-clas
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Bernhard Gschaider
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Check out the inletOutlet-class of boundary conditions (fixedValue for inflow, zeroGradient for outflow) in the table 6.4 of the UserGuide. Use that for the temperature.
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Old   October 15, 2007, 07:55
Default Thanks! Thought they were o
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Thought they were only applicable to pressure, but seems to be running...

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