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Why does this mesh crash?

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Old   August 2, 2017, 06:14
Default Why does this mesh crash?
  #1
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Zach
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convertToMeters 1;

vertices
(
(0 0 0)
(0 -1 -1)
(0 1 -1)
(0 -1 1)
(0 1 1)
(1 0 0)
(1 -1 -1)
(1 1 -1)
(1 -1 1)
(1 1 1)
);

blocks
(
prism (0 1 2 5 6 7) (1 1 1) simpleGrading (1 1 1)
prism (0 2 4 5 7 9) (1 1 1) simpleGrading (1 1 1)
prism (0 4 3 5 9 8) (1 1 1) simpleGrading (1 1 1)
prism (0 3 1 5 8 6) (1 1 1) simpleGrading (1 1 1)
);

edges
(
arc 1 2 (0 0 -1.41421356)
arc 2 4 (0 1.41421356 0)
arc 4 3 (0 0 1.41421356)
arc 3 1 (0 -1.41421356 0)
arc 6 7 (1 0 -1.41421356)
arc 7 9 (1 1.41421356 0)
arc 9 8 (1 0 1.41421356)
arc 8 6 (1 -1.41421356 0)
);

boundary
(
inlet
{
type patch;
faces
(
);
}
outlet
{
type patch;
faces
(
);
}
bottom
{
type symmetryPlane;
faces
(
(1 6 7 2)
);
}
top
{
type symmetryPlane;
faces
(
(3 8 9 4)
);
}
left
{
type symmetryPlane;
faces
(
(0 1 2)
(0 2 4)
(0 4 3)
(0 3 1)
);
}
right
{
type symmetryPlane;
faces
(
(5 6 7)
(5 7 9)
(5 9 8)
(5 8 6)
);
}
front
{
type symmetryPlane;
faces
(
(1 6 8 3)
);
}
back
{
type symmetryPlane;
faces
(
(7 2 4 9)
);
}
obstacle
{
type patch;
faces
(
);
}
);

mergePatchPairs
(
);
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Old   August 2, 2017, 23:04
Default
  #2
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Hi,

I have no idea which version of OpenFOAM you are using, but in most ones the block type HAS to be hex.

In order to generate a prism, you would define it as a hex and have some vertices repeating.

So for something like this:
Code:
prism (0 1 2 5 6 7) (1 1 1) simpleGrading (1 1 1)
One possible solution is:
Code:
hex (0 1 2 0 5 6 7 5) (1 1 1) simpleGrading (1 1 1)
I noticed that you have arcs defined. You will not be able to view your arcs with just 1 cell. So increase the cell count to be able to capture your arcs.

Cheers,
Antimony
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Old   August 3, 2017, 00:07
Default Additional Question
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Zach
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Thanks for the help. The lab manual I was looking at had prism as a type of shape that can be used. Would just 2 cells work for arcs, or do I need like 100? I know more than 1000 can cause a crash.
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Old   August 3, 2017, 01:11
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Hi,

I don't think you need 100 or 1000. At the minimum I would suggest at least 3 or 4. But then again, it depends on how accurately you want the arc to be captured.

Cheers,
Antimony
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Old   August 4, 2017, 13:07
Default Are pyramids valid?
  #5
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Is pyr (1 2 3 4 5) valid or does this also have to be converted to a hex?
Would the solution be hex (1 2 3 4 5 5 5 5)?
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Old   August 6, 2017, 22:07
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Hi,

AFAIK, the only supported type in blocks is hex. So yes, you would have to switch to a hex definition like what you have mentioned.

Cheers,
Antimony
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