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alpha1 is unbounded

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Old   October 17, 2012, 04:48
Default alpha1 is unbounded
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Gerhard Holzinger
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I am trying to simulate a bubble column with twoPhaseEulerFoam. When running my case alpha1 reaches values that should not be possible.

Courant Number mean: 0.00734422 max: 0.637501
Max Ur Courant Number = 0.453228
Time = 0.675

MULES: Solving for alpha1
Dispersed phase volume fraction = 0.000455625  Min(alpha1) = -0.00187942  Max(alpha1) = 1
MULES: Solving for alpha1
Dispersed phase volume fraction = 0.000455625  Min(alpha1) = -0.540265  Max(alpha1) = 1
There is some checker-boarding next to the inlet. Does anyone have some tips how to eliminate that.
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File Type: jpg checkerBoardingAlpha1.jpg (12.4 KB, 28 views)
Attached Files
File Type: gz bubbleColumn.tar.gz (5.7 KB, 6 views)
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Old   October 17, 2012, 05:25
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Anton Kidess
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Try using a much smaller time step.
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