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wingMotion2D Tutorial Questions

Hi all

I'm fairly new to OF
I'm working with Open Foam 1.7.0 in CAE Linux 2010

I am trying to understand the subject of Dynamic Meshing in open Foam, I have been looking at the tutorial wingmotion in pimpleDyMFoam. Although I would like to check to see if the correct things happened when I executed it.

I executed by moving to the directory,

Code:

cd $FOAM_RUN/tutorials/incompressible/pimpleDyMFoam/wingMotion

Then I entered

Code:

./Allrun

The following ran before it popped me back out in the terminal normally without any error messages

Code:

Running blockMesh on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion_snappyHexMesh

 Running snappyHexMesh on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion_snappyHexMesh

 Running extrudeMesh on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_simpleFoam

 Running autoPatch on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_simpleFoam

 Running createPatch on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_simpleFoam

 Running simpleFoam on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_simpleFoam

 Running mapFields on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_pimpleDyMFoam

 Running decomposePar on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_pimpleDyMFoam

 Running pimpleDyMFoam in parallel on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_pimpleDyMFoam using 3 processes

 Running reconstructPar on run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_pimpleDyMFoam

When I checked the sub folders, as I had expected the wingMotion2D_simpleFoam contained the time data folders running up to 3000,
however the wingMotion2D_pimpleDyMFoam only contained 2 time data folders.

Then when I checked the results in paraFoam, the _simpleFoam results showed no evidence of mesh change.

The pimpleDyMFoam
results caused parafoam to exit with the following message

Code:

--> FOAM FATAL IO ERROR: 

Expected a ')' while reading VectorSpace<Form, Cmpt, nCmpt>, found on line 16330 an error



file: /home/droper1/OpenFOAM/droper1-1.7.0/run/tutorials/incompressible/pimpleDyMFoam/wingMotion/wingMotion2D_pimpleDyMFoam/0.005/polyMesh/points at line 16330.



    From function Istream::readEnd(const char*)

    in file db/IOstreams/IOstreams/Istream.C at line 103.



FOAM exiting

Is this something I have done wrong... what should the outcome have been?

Regards Dandalf

Having inspected the case file closely, I have noticed that it is set up to run on three processors in parallel, however I am working with a Dual core processor

I believe this may be the root of my problem,
Although I don't know too much about parallel processing, it looks like I can fix this by changing the Allrun file to read

Code:

runParallel pimpleDyMFoam 2

and by changing decomposeParDict
to read

Code:

numberOfSubdomains 2;



method          simple;



simpleCoeffs

{

    n               ( 1 2 1 );

    delta           0.001;

}



hierarchicalCoeffs

{

    n               ( 2 2 1 );

    delta           0.001;

    order           xyz;

}



manualCoeffs

{

    dataFile        "cellDecomposition";

}



metisCoeffs

{

}

I am going to try it again and see what happens

Ok I got it to work... It tuns out I simply ran out of hard drive space the first time.

I have a few questions regarding the case.

In the dynamicMeshDict
the diffusivity variable presumably determines how geometry distortions are diffused throughout the grid.

It is currently set to inverseDistance with regards to a single geometric object. Is it possible to set it to inverseDistance with regards to multiple geometric objects?

Secondly in the pointDisplacment file, the case uses the sixDoFRigidBodyDisplacment,
are there any notes available on this boundaryField type, and is it possible to create a hinged joint between two geometric objects using it?

I would appreciate any help people can give me.

Dandalf