[moodkiller]

Hi
I have been trying to solve the velocity of an extruded rectangle.
I did everything up until Setup and when I tried to solve it this error came up.
Anyone has suggestions to what I could do?

ERROR #002100048 has occurred in subroutine SU_BNEXT. |
| Message: |
| All vertices for a fluid domain lie on boundaries. This is |
| considered to be a fatal error because control volume gradients |
| cannot be calculated, leading to serious discretization error. |
| |
| A common cause for this error is a mesh which is only one |
| element thick, without symmetry or 1:1 periodicity on the lateral |
| boundaries. If you have this situation, and the domain is |
| two-dimensional, please change the lateral boundary conditions |
| to symmetry or 1:1 periodicity. Alternatively, for |
| three-dimensional simulations, please ensure that your mesh |
| has at least two elements across. |
| |
| Execution is terminating. This error message can be bypassed by |
| setting the expert parameter 'boundary vertex check = f', but |
| be aware that doing so may lead to significant solution error. |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| The ANSYS CFX solver exited with return code 1. No results file |
| has been created. |
+--------------------------------------------------------------------+

End of solution stage.

+--------------------------------------------------------------------+
| For CFX runs launched from Workbench, the final locations of |
| directories and files generated may differ from those shown. |
+--------------------------------------------------------------------+


This run of the ANSYS CFX Solver has finished.

[ghorrocks]

The error message is very clear, tells you exactly what the problem is and how to fix it. So my suggestion would be to read the error message and do what it says.

[moodkiller]

I just need help interpreting what the message means. Yes, I did read the message but still don't know how to do it.

[ghorrocks]

You have a domain where all the nodes lie on the boundary - so no internal nodes. You can only do this under a limited set of circumstances.

If you are intending doing a 3D simulation the fix is to remesh so that you have internal nodes in the domain. If you are intending doing another type of simulation then please explain what you are trying to do.

[moodkiller]

So basically so far I have drawn a rectangle, then i extruded it. I applied a fine mesh (i tried medium and coarse before same errors), then I created an inlet boundary with velocity of 0.00333 m/s, then I created an outlet with 0 Pa pressure. I also modified the density and viscosity.
So if that's the case, where can I go to fix the internal nodes in the domain?

[ghorrocks]

nodes = mesh. So you need to fix the mesh.

If you can't find the problem post an image of your mesh on the forum.

[moodkiller]

http://tinypic.com/r/52bei1/9

[-Maxim-]

This doesn't seem like a fine mesh to me...

A common cause for this error is a mesh which is only one element thick

That's exactly your problem. You need to refine your mesh so that you have at least some cells that are not directly part of the wall.