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Old   April 3, 2012, 12:35
Default simple Foam empty solution
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Debb
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I'm trying a channel (with one two bends) in simpleFoam, it seems to be running without errors but when I look at the results in paraView I only see the inlet and outlet vectors, and nothing is happening in the actual channel throughout the 20 second run

my U conditions are the following:

internalField uniform ( 0 0 0 );

boundaryField
{

inlet
{
type fixedValue;
value uniform ( 0.2 0 0 );
}
Wall1 //all the walls are defined in the same manner
{
type fixedValue;
value uniform ( 0 0 0 );
}
Outlet
{
type fixedValue;
value uniform ( 0 -0.2 0 );
}

is there anything obvious that I am missing here?

any help would be much appreciated.
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Old   April 3, 2012, 13:40
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arash
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Hi,
I think the problem stems from the fact that setting a fixed value for velocity in outlets makes the solution unstable and may result in strange solutions. you may try runnig the case with zero gradient B.C. for velocity in the outlet.
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Old   April 3, 2012, 16:03
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thanks for the info, I changed the outlet value as per your instructions but I'm still getting an almost empty solution, and most of the glyphs are outside of the volume, coming off a wall, rather than the outlet, so I'm assuming that my solution is still unstable

are there any "tricks" that might be useful here to get a stable solution?
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Old   April 4, 2012, 01:52
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kid
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Hello,
We would require more inputs like U,p,RASProperties files.
Use dropbox/box account and use a public link to the picture/file to share the full case.

Hope you co-operate.

regards
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Old   April 4, 2012, 02:33
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Alberto Passalacqua
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How did you generate the mesh? I am asking because I noticed a similar issue with one imported mesh.
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Old   April 4, 2012, 09:06
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I've attached my files. I generated the mesh using blockMesh. This morning I found an error in my blockMesh file and feeling a bit dumb about it (was missing a wall, and I only figured this out by building the geometry out of cardboard and labeling all the faces).

But still not really showing much within the geometry after I run a simulation.
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File Type: zip channel.zip (6.3 KB, 2 views)
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Old   April 4, 2012, 17:20
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I've uploaded the complete file folder to drop box https://www.dropbox.com/sh/1o5m7ukgl2fqkaf/qqbzctfKKT
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