[Seb_Ve]

Hello all,

I am quite new to openFoam and I am having some trouble with my mesh. The checkMesh function tells me that I am having 3 errors with my mesh. According to my researches the urgent problem is the "Error in face pyramids". I checked my blockMeshDict almost 100 times but I didn't find the mistake. Maybe someone can help me.

My blockMeshDict:

/*-------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 4.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object blockMeshDict;
}

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

convertToMeters 0.001;

vertices
(
(0 0 0) //0
(110 0 0) //1
(125 0 0)
(345 0 0)

(345 1 0) //4
(125 1 0)
(110 1 0)
(0 1 0)

(0 0 36.53) //8
(110 0 36.53)
(125 0 34.6)
(345 0 34.6)

(345 1 34.6) //12
(125 1 34.6)
(110 1 36.53)
(0 1 36.53)

(0 0 43.8) //16
(117.27 0 43.8)
(345 0 43.8)
(345 1 43.8)

(117.27 1 43.8) //20
(0 1 43.8)
(0 0 44.2)
(117.27 0 44.2)

(345 0 44.2) //24
(345 1 44.2)
(117.27 1 44.2)
(0 1 44.2)

(110 0 43.8) //28
(110 1 43.8)
(110 0 44.2)
(110 1 44.2)

);

blocks
(
hex (0 1 6 7 8 9 14 15) (80 1 100) simpleGrading (1 1 1) //0
hex (8 9 14 15 16 28 29 21) (80 1 40) simpleGrading (1 1 0.2) //1
hex (9 9 14 14 28 17 20 29) (60 1 40) simpleGrading (
((0.7 0.9 3) (0.3 0.1 3)
)
1
0.2
) //2
//hex (8 9 14 15 16 17 20 21) (100 1 90) simpleGrading (1 1 1)
hex (16 28 29 21 22 30 31 27) (80 1 10) simpleGrading (1 1 1) //3
hex (28 17 20 29 30 23 26 31) (60 1 10) simpleGrading (
((0.7 0.9 3)(0.3 0.1 3)
)
1
1
) //4

//hex (16 17 20 21 22 23 26 27) (100 1 60) simpleGrading (1 1 1)
hex (17 18 19 20 23 24 25 26) (100 1 10) simplegrading (1 1 1) //5
hex (10 11 12 13 17 18 19 20) (100 1 90) simpleGrading (1 1 1) //6
hex (2 3 4 5 10 11 12 13) (100 1 100) simpleGrading (1 1 1) //7

);

edges
(
arc 9 17 (113.635 0 42.826)
arc 14 20 (113.635 1 42.826)
);

boundary
(

inlet
{
type patch;
faces
(
(0 7 15 8)
(8 15 21 16)
(16 21 27 22)
);
}

outlet
{
type patch;
faces
(
(3 4 12 11)
(11 12 19 18)
(18 19 25 24)
);
}

walls
{
type wall;
faces
(
(1 6 14 9)
(2 5 13 10)
(0 1 6 7)
(2 3 4 5)
(9 14 20 17) // vielleicht falsch
(10 13 20 17)// vielleicht falsch
(22 30 31 27)
(30 23 26 31)
(23 24 25 26)
);
}
empty
{
type empty;
faces
(
(0 1 9 8)
(8 9 28 16)
(9 9 17 28)
(16 28 30 22)
(28 17 23 30)
(2 3 11 10)
(10 11 18 17)
(17 18 24 23)
(7 6 14 15)
(15 14 29 21)
(21 29 31 27)
(29 20 26 31)
(14 14 20 29)
(5 4 12 13)
(13 12 19 20)
(20 19 25 26)
);
}

);

// ************************************************** *********************** //

The checkMesh Message:

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 71042
internal points: 0
faces: 140520
internal faces: 69420
cells: 35000
faces per cell: 5.99829
boundary patches: 5
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 34940
prisms: 60
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
inlet 150 302 ok (non-closed singly connected)
outlet 200 402 ok (non-closed singly connected)
walls 750 1504 ok (non-closed singly connected)
empty 70000 71042 ok (non-closed singly connected)
defaultFaces 0 0 ok (empty)

Checking geometry...
Overall domain bounding box (0 0 0) (0.345 0.001 0.0442)
Mesh has 2 geometric (non-empty/wedge) directions (1 0 1)
Mesh has 2 solution (non-empty) directions (1 0 1)
All edges aligned with or perpendicular to non-empty directions.
Boundary openness (7.90954e-19 3.57202e-13 7.55662e-17) OK.
***High aspect ratio cells found, Max aspect ratio: 2289.54, number of cells 2
<<Writing 2 cells with high aspect ratio to set highAspectRatioCells
Minimum face area = 2.90059e-11. Maximum face area = 2.2773e-06. Face area magnitudes OK.
Min volume = 2.90059e-14. Max volume = 7.612e-10. Total volume = 1.46389e-05. Cell volumes OK.
Mesh non-orthogonality Max: 88.839 average: 18.4643
*Number of severely non-orthogonal (> 70 degrees) faces: 1101.
Non-orthogonality check OK.
<<Writing 1101 non-orthogonal faces to set nonOrthoFaces
***Error in face pyramids: 1 faces are incorrectly oriented.
<<Writing 1 faces with incorrect orientation to set wrongOrientedFaces
***Max skewness = 6.57204, 7 highly skew faces detected which may impair the quality of the results
<<Writing 7 skew faces to set skewFaces
Coupled point location match (average 0) OK.

Failed 3 mesh checks.

End


My geometrie:



Thanks in advance!

[simrego]

Your blockMesh is ok. I mean you have no errors in it. But the mesh what you told it to generate is really bad. You should try to figure out a new blocking structure because this mesh has a really really poor quality. So much distorted cells and huge jumps in the cell sizes.



Screenshot from 2018-05-31 15-35-58.png Screenshot from 2018-05-31 15-36-15.png Screenshot from 2018-05-31 15-36-50.png