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lars. June 22, 2010 09:33

calculate difference between runs
Hi all,
I am sure it is very simple, but...

I am running the same case with different settings in fvSchemes and fvSolution, once in caseDirA and once in caseDirB. I would like to study how these settings affect the solution accuracy. How can I visualize the difference between the two runs in paraFoam?

I can open both the results from caseDirA and from caseDirB in paraFoam. But the Calculator filter works only on the selected dataset, not among two different datasets.

Does OpenFOAM come with utilities to write the difference in some variable T between two cases? Like foamCalc can do some vector algebra (on a single case)?


Axel_T August 16, 2010 12:56

Hi Lars,

it really seems to be a simple job to do, but I didn't found out the trick, either.

My solution was to write a scilab-script (almost similiar to MATLAB, but open-source) that takes the fielddata from both cases, calculates the difference and stores it in a new file. Then I copied the case-dir and replaced the fielddata with the calculated ones and launched paraview.

It really couldn't be more complicated!

So, if you meanwhile found the trick with the paraview-calculator, I'd be glad if you could post it here.


giack January 12, 2015 07:50

Hi to all,
did you manage to find the solution at the problem? I'm trying to do the same but I'm not able to do it...


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