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Old   February 6, 2012, 06:58
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albert
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hi,

im modeling a flow in a channel going upwards through a porous media(1cm thick), instead of doing it throug the perforated plate. The velocity profile i get at the beginning of the channel is very discontinuous, being negative and positive, and very irregular.

Could someone help me to find a solution in order to reduce this irregularities and have only positive upwards flow?

Thanks!
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Old   February 6, 2012, 20:10
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Are you sure you have adequately converged?
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Old   February 7, 2012, 04:04
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actuially i had to stop the simulation since they were very long. Nevertheless the masas and momentum were not changing anymore. What parameter should i change to make it converge?
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Old   February 7, 2012, 04:14
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I dont know if it is your mistake, but last week i was facing a similar problem and the (stupid) mistake was that i wasnt using double precision. If not, try to refine the mesh. Also check that the bouyancy is properly defined if you used it.
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Old   February 7, 2012, 05:37
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what do you mean with double precision?
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Old   February 7, 2012, 06:04
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I meant that in the Solver Manager (called Solution in Workbench) you can choose which precision you want to use, Run priority and other stuff.

When you open the Solver Manager, in the Define Run window, there are two folders: Solver and Interpolator. I marked the Double Precision Override in both of them and then I had no problems anymore.
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