ERROR #002100013 has occurred in subroutine Chk_Sp
 

Hi all,

I am using cfx5.7.1 to do a two modelling. I used symmetry boundaries. Because I don't want more cells on the third direction so the physical distance on the third direction is very small (smaller than the larger cell dimension). Ideally, when I was using structured mesh, only one cell along the third direction and now I have to use unstructured mesh due to the geometry reasons.

There was no problem when I was generating the mesh using ICEM and set the boundary conditions in cfx-pre, only when I run it I got this error (see below). I tried to refine the mesh and used the expert parameters it suggested, but it keeps telling me this.

Does this mean I do need more cells on the third direction in order to make the plane to be a 'strict plane'? If there are more cells in the third direction, am I going to have 3D effects for the calculation? I mean, parameters in the third direction won't be uniform as it is assumed to be.

Thanks for your help

Regards Yingchun

Followed the error message:

ERROR #002100013 has occurred in subroutine Chk_Splane. Message: The symmetry boundary condition requires that the boundary patch mesh faces form a plane or axis. However, face set 14 in the symmetry boundary patch

SymFluid111

is not in a strict plane, which means that at least one of its faces is not parallel to the others. To make the solver run you can do one of the following:

(1) Make sure that this symmetry boundary patch is in a plane or

axis by checking and regenerating the mesh.

(2) If the symmetry boundary patch is an axis rather than a

plane, change the tolerance of the degeneracy check by

increasing the value of the Solver Expert Parameter

'degeneracy check tolerance' (the default value is 1.e-4).

(3) Increase the value of the Solver Expert Parameter

'vector parallel tolerance' (the default value is 1 deg.).

Note that the accuracy of the symmetry condition may decrease

as the tolerance is increased. This is because the tolerance

is the number of degrees that a mesh face normal is allowed

to deviate from the average normal for the entire face set.

Hello,
did you fix the problem?

The error this post is about is a simple one. You have to make sure a symmetry plane is actually a plane. The error usually comes about because:
1) You have put multiple symettry planes in one boundary. You need to put them each in their own symmetry plane
2) You have defined a curved surface to be a symmetry plane - you can't do this
or
3) A meshing error has put a few stray elements into a symmetry plane. THis can happen in ICEM with the way it meshes, the fix is to manually check and fix the symmetry plane elements.

same problem about symmetry
 

I'm keeping get the following error every time I try to refine the mesh. This time I just increase the Prismen layer number from 6 to 7, and with 6 the solver has worked. I#m wondering if it's because of the thickness of the Domain, i'm calculating a 1,2mx2.85m rectangular Domain with airfoil in it. The thickness of the Domain is only 0.01m. But it also worked for 6 Prismen layer?

The symmetry boundary condition requires that the boundary patch |
| mesh faces form a plane or axis. However, face set 3 in the |
| symmetry boundary patch

Symmetry

| is not in a strict plane, which means that at least one of its |
| faces is not parallel to the others. To make the solver run |
| you can do one of the following:

I met this probelm really frequently, not only for the structured mesh but also for the unstructred mesh: I can't see many mesh in wrong boudary surfaces and thus don't know how to fix it manuelly.

Did you fix your Problem now? and how?

Load your model in CFD-Post (or if it did not generate an output file, in your mesher) and find the faces in the symmetry face which are off the plane. It is a very simple error, but it can take some hunting to find the problem elements.