[lentschi]

Hello community,

I have 2 perfectly matching and non-rotating/moving blocks, which are coupled by a mixingPlane Interface.

During calculation I always get an Floating Point Exception error. I have tried many different settings (and copied the settings from a mixingPlane tutorial) but get this error again:

Create mesh for time = 0

Initializing the mixingPlane interpolator between master/shadow patches: STAT1/STAT2
Reading field p

Reading field U

Calculating potential flow
CG: Solving for p, Initial residual = 1, Final residual = 0.00992722, No Iterations 82
continuity error = 9.22837e-06
Floating point exception (core dumped)

My boundary file looks like this:

6
(
INLET
{
type patch;
nFaces 171;
startFace 27788;
}
STAT1
{
type mixingPlane;
nFaces 171;
startFace 27959;
shadowPatch STAT2;
zone STAT1ZONE;
coordinateSystem
{
type cylindrical;
name mixingCS;
origin (0 0 0);
e1 (0 0 1); //Direction of Streamlines in z-Direction
e3 (1 0 0);
}
ribbonPatch
{
sweepAxis Theta;
stackAxis Z;
discretisation bothPatches;
}

}
WALL1
{
type wall;
nFaces 1624;
startFace 28130;
}
OUTLET
{
type patch;
nFaces 171;
startFace 29754;
}
STAT2
{
type mixingPlane;
nFaces 171;
startFace 29925;
shadowPatch STAT1;
zone STAT2ZONE;

}
WALL2
{
type wall;
nFaces 1624;
startFace 30096;
}
)

The mesh is ok, as can be seen in checkMesh:

Checking topology...
Boundary definition OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
*Number of regions: 2
The mesh has multiple regions which are not connected by any face.
<<Writing region information to "0/cellToRegion"

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Area [m^2] Surface topology
INLET 171 200 0.1 ok (non-closed singly connected)
STAT1 171 200 0.1 ok (non-closed singly connected)
WALL1 1624 1680 6.6 ok (non-closed singly connected)
OUTLET 171 200 0.1 ok (non-closed singly connected)
STAT2 171 200 0.1 ok (non-closed singly connected)
WALL2 1624 1680 6.6 ok (non-closed singly connected)

Checking geometry...
This is a 3-D mesh
Overall domain bounding box (-3.46945e-18 -2.77556e-17 0) (0.1 1 6)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Mesh (non-empty, non-wedge) dimensions 3
Boundary openness (5.95673e-17 -9.5346e-18 2.69053e-18) Threshold = 1e-06 OK.
Max cell openness = 1.96445e-16 OK.
Max aspect ratio = 13.0944 OK.
Minumum face area = 0.0001. Maximum face area = 0.0140221. Face area magnitudes OK.
Min volume = 2e-06. Max volume = 0.000160253. Total volume = 0.6. Cell volumes OK.
Mesh non-orthogonality Max: 0 average: 0 Threshold = 70
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 1.24444e-09 OK.

Mesh OK.


Has anyone an idea to solve this problem?

Thanks in advance.

Regards,
Markus

[lentschi]

Problem solved!

Definition problem in the boundary file!

[sivakumar]

hi don lenardo,
I am using MRFSimpleFoam, 1/8 th of the fan. So far I am using Conformal Mesh, but now I want to reduce the computational time by using AMI interface,

my questions are:

is it possible in MRFSimpleFoam? I have attached the fig, please have a look. (the fan is in the middle)

I have edited (manually, I didt use createPatch utility) as follows:

constant/polyMesh/boundary

AMI4
{
type cyclicAMI;
nFaces 13000;
startFace 40391000;
neighbourPatch AMI3;
bridgeOverlap false;
}
AMI3
{
type cyclicAMI;
nFaces 26000;
startFace 40404000;
neighbourPatch AMI4;
bridgeOverlap false;
}
AMI2
{
type cyclicAMI;
nFaces 23400;
startFace 40430000;
neighbourPatch AMI1;
bridgeOverlap false;
}
AMI1
{
type cyclicAMI;
nFaces 13000;
startFace 40453400;
neighbourPatch AMI2;
bridgeOverlap false;
}

when I run check Mesh, I am getting the warning message as you given in the first post.

Can you please help me solve the problem?

I am using OF-2.1.1

mixing plane, is it available in OF2.1.1?

can you please explain the procedure?




kind regards,
Sivakumar

[lentschi]

Hello Sivakumar,

Mixing Plane is not available in OF 2.1!
Re-check your boundary file - maybe the boundaries are incorrectly defined and AMI 1 is not the neighbour of AMI2 (and AMI3 to AMI4 respectively).

Additionally, you have to add the following lines to each AMI-boundary:

transform noOrdering;
matchTolerance 0.001;


Hopefully this will help!

//Markus