calculate difference between runs

lars. · June 22, 2010, 09:33

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)?

Thx
Lars

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.

regards,
Axel

giack · January 12, 2015, 06:50

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...

Regards

June 22, 2010, 09:33	calculate difference between runs	#1
lars. New Member Lasse Join Date: Jun 2010 Posts: 5 Rep Power: 15	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)? Thx Lars

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August 16, 2010, 12:56		#2
Axel_T New Member Axel Tietjen Join Date: Dec 2009 Location: Hamburg, Germany Posts: 19 Rep Power: 16	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. regards, Axel

January 12, 2015, 06:50		#3
giack Member Join Date: Mar 2013 Posts: 98 Rep Power: 13	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... Regards