[Redrakham]

I want to solve vortex-induced vibration of a cylinder in a duct. I have solved the flow in a duct without the cylinder and then I want to map the fields from the cylinder-less problem to the problem with the cylinder in a duct. Both the geometries have same dimensions. But when I tried to map the fields the error comes:
--> FOAM FATAL ERROR:
Incompatible meshes: different number of patches, fromMesh = 6, toMesh = 7

I think the reason is with the cylinder case I have to add the cylinder patch. Is there anyway to map the fields with different number of patches?


I have attached the two meshes:
without_cylinder.jpeg with_cylinder.jpeg


Thank you in advance.

[tomf]

Hi Redrakham,

mapFields can be used in various situations. I think you could learn from the clipped cavity tutorial.

I think such a situation would apply for your case as well, where the cylinder patch would be part of the cuttingPatches in mapFieldsDict.

Hope this helps.
Tom

[Redrakham]

I have tried this but got the same error.

[tomf]

Well it would be helpful if you can share exactly what you typed, how your mapFieldsDict looks like and what the complete output says. Otherwise we can only guess what is going on.

Cheers,
Tom

[Redrakham]

This is my mapFieldsDict:


FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object mapFieldsDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

patchMap ( );

cuttingPatches (cylinder1);


My patch name for cylinder is cylinder1.


This is the error I got:


Build : v1906 OPENFOAM=1906
Arch : "LSB;label=32;scalar=64"
Exec : mapFields -consistent -sourceTime latestTime ../without_cylinder1
Date : Mar 23 2023
Time : 15:10:01
Host : abhi
PID : 24097
I/O : uncollated
Case : /home/abhi/Turbulent/snappy_confined_2D/with_cylinder
nProcs : 1
trapFpe: Floating point exception trapping enabled (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 10)
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Source: "/home/abhi/Turbulent/snappy_confined_2D" "without_cylinder1"
Target: "/home/abhi/Turbulent/snappy_confined_2D" "with_cylinder"

Create databases as time

Source time: 600
Target time: 0
Create meshes

Source mesh size: 161280 Target mesh size: 385248



--> FOAM FATAL ERROR:
Incompatible meshes: different number of patches, fromMesh = 6, toMesh = 7

From function Foam::meshToMesh0::meshToMesh0(const Foam::fvMesh&, const Foam::fvMesh&)
in file meshToMesh0/meshToMesh0.C at line 134.

FOAM exiting


If you want I can share the whole case.

[tomf]

Hi,

Thanks for the extra information. Your problem is the consistent option. That is only valid if your geometry and boundary conditions are exactly the same. But as you have the cylinder, the geometry is no longer exactly the same.

You may need to add all other patches to patchMap in you mapFieldsDict to copy the information on them from your empty domain case.

Best Regards,
Tom

[Redrakham]

Thank you for your prompt reply. If I made the two geometries identical with one case having cylinder and the other have not then it is running all right. Now if I want to map the field of without cylinder case to the case of having cylinder with bigger geometry then it shows error:
--> FOAM FATAL IO ERROR:

size 385248 is not equal to the given value of 633468

file: /home/abhi/Turbulent/snappy_confined_2D/with_cylinder/0/nut

From function Foam::Field<Type>::Field(const Foam::word&, const Foam::dictionary&, Foam::label) [with Type = double; Foam::label = int]

in file /home/abhi/OpenFOAM-v1906/src/OpenFOAM/lnInclude/Field.C at line 221



My mapFieldsDict is Now:


fields (U);
patchMap ();



cuttingPatches (

cylinder1
top
bottom
front
back
inlet
outlet
);
Can you please help me with that.

[Redrakham]

Here is my case files:
with_cylinder.zip
without_cylinder1.zip