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Initialize a random velocity field with funkySetFields

Posted November 14, 2016 at 13:31 by kindle
Updated February 23, 2017 at 04:05 by kindle

This is useful for me

Quote:

Originally Posted by Andrea1984

Hi,

I would like to inizialize a random velocity field with funkySetFields. Is it possible?

I've tried something like

{
field U;
expression "vector (0.005*rand(), 0.005*rand(), 0.005*rand())";
}

Do you think this should work?

Thanks in advance

Andrea

And this is link for swak
http://openfoamwiki.net/index.php/Contrib/swak4Foam/Example_initRandomVelocity...

kindle

New Member

Posted in Pre-processing

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blockMesh non-uniform grid

Posted November 10, 2016 at 14:32 by kindle

This way we can estimate already order of magnitude.

Quote:

Originally Posted by hjasak

Actually, the grading factor in blockMesh is defined as the ratio of the last to first cell size, which is much better behaved that defining the number of cells and the geometric expansion ratio. I suppose we have both done the same thing :-)

Hrv

kindle

New Member

Posted in Pre-processing

Views 2361 Comments 0 kindle is offline

Customized fvOptions-class for momentum source: no rule to make target

Posted November 10, 2016 at 13:00 by kindle
Updated February 23, 2017 at 04:06 by kindle

Another one

Quote:

Originally Posted by potentialFoam

Dear Foamers,

I would like to create my own fvOptions-class to introduce a momentum source term. (Unfortunately, none of the existing classes help me.)

Approach:
I copied the 'actuationDiskSource'-folder,
I renamed the files and names inside from 'actuationDisk...' to 'newSource...',
I added the 'newSource.C'-file in '$FOAM_SRC/fvOptions/Make/files',
then I tried to compile it with 'wmake' and 'wmake libso'.

...

kindle

New Member

Posted in programming

Views 1051 Comments 0 kindle is offline

channel395 : Using fvOptions to add a momentum source

Posted November 10, 2016 at 12:57 by kindle
Updated October 16, 2017 at 06:15 by kindle

The problem in channel395

Quote:

Originally Posted by huangxianbei

After a period of searching , I continue my calculation for a much longer time, the velocity at the domain center oscillating around 0.15m/s(the Ubar=0.1335m/s), about 1.1times. So this is exactly what it should be. The first problem is solved.

However, I'm still not quite understand the second problem. How can we initialize the p ,nusgs fields? Or my misunderstanding, just perturbU required for the velocity field?

And fvOptions in channel395...

kindle

New Member

Posted in programming

Views 1650 Comments 0 kindle is offline

paraview-python

Posted November 9, 2016 at 06:14 by kindle
Updated November 9, 2016 at 10:50 by kindle

Requirement : paraview not the wrapper paraFoam of Openfoam [maybe because it is partially compiled].

1. start paraview
2. tools - start trace
3. openfile (with *.foam)
4. ...
5. save image etc.
6. stop trace and a window will pop out with python script
7. creat pythonScript.py
8. run with pvpython (executable in paraview) or add on first line like #!/opt/ParaView-4.1.0-Linux-64bit/bin/pvpython
9. chmod +x pythonScript.py ; execute pythonScript.py...

kindle

New Member

Posted in Post-processing

Views 1023 Comments 0 kindle is offline