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multiphase... solid volume fraction anomaly

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Old   April 8, 2008, 23:09
Default multiphase... solid volume fraction anomaly
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Tim
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Hi,

When I run a multiphase simulation and proces the results, a contour of the volume fraction of the solid particles results in areas where the volume solid fraction is 1, even though I have put in a maximum volume fraction of 0.62. I have designated seperate velocity fields for the solid particles and the continuous fluid, could this be why? Here are some of the details.

air continuous fluid solid particles 1 mm diameter dispersed, 50% volume fraction k-epsilon turbulence model sato enhanced eddy viscosity restitution coefficient 0.5 gidaspow solid pressure model

Thanks, Tim.
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Old   February 13, 2012, 06:47
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Hi I am having the same problem too! The initial static solid volume fraction of the bed is equals to 1 despite setting my solid as a dispersed solid. Can some1 please help me out with this issue? Many thanks.
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Old   February 13, 2012, 11:45
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I'm no expert, Iíve only dealt with fluids, but I'd say the simulation did not accept your input and hence you got 1 for one medium and 0 for the other.
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Old   February 13, 2012, 14:57
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Max
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solver cant guarantee to keep below packing limit. period.
(thats what i got out of thr doc, but it was some time ago...)
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Old   February 14, 2012, 05:01
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Hmm actually I was thinking whether it has got anything to do with the definition of the "solid volume fraction". Is it the absolute value or is it the value relative to the maximum packing? hmmm.
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