Transforming results to OpenFOAM format

astein · May 2, 2013, 11:25

Dear Foamers,

do you know any option to transform results (e.g. from CFX, CGNS, Tecplot) to the OpenFOAM format?
I'd like to postprocess some results with OpenFOAM tools, however I could not find a way to transform the results.

Running cgnsToFoam converts the mesh, but the not the results themselvers.

Any help is welcome, thanks a lot in advance!

wyldckat · May 2, 2013, 11:37

Greetings astein,

Since that's rarely used, there are very few ways to convert results from other applications to OpenFOAM.

The only one I know about is fluentDataToFoam and it's part of Extend's variant OpenFOAM 1.6-ext: http://www.cfd-online.com/Forums/ope...of2-1-1-a.html

And don't forget that you already need to have the mesh ready on the OpenFOAM case, otherwise there is no mesh to place the results inside it...

And the big question is: if you have Tecplot, why do you want to use OpenFOAM for post-processing data?

Best regards,
Bruno

astein · May 2, 2013, 12:13

Thanks for your fast answerand the hint to fluentDataToFoam!
With "postprocessing", I meant stuff like doing further compuations on the mesh based on given results. I have those methods available in OpenFOAM, but would like to run them on CFX results.

Regarding fluentDataToFoam, I just gave it a try: I imported the .res file in Fluent and saved as a .cas - is that correct? (I tried both, binary and ASCII)

starting fluentDataToFoam in a correct Foam case with
"fluentDataToFoam testcase2.cas" for the ASCII-dat,
starts working, but stops with:
#################################
--> FOAM FATAL IO ERROR:
Attempt to get back from bad stream

file: IStringStream.sourceFile at line 0.

From function void Istream::getBack(token&)
in file db/IOstreams/IOstreams/Istream.C at line 39.

FOAM exiting
#################################

Any hints for this problem or other ideas to transform the results?

wyldckat · May 2, 2013, 12:25

I guess you didn't read carefully that whole thread...
Check this post, which is referenced on the first thread I had mentioned: http://www.cfd-online.com/Forums/ope...tml#post412947 post #4

astein · May 2, 2013, 12:40

Thanks again for your fast reply!

I'm trying to use the utility in a working 1.6-ext, having fluentDataToFoam compiled correctly - therefore I wouldn't expect any problems on this side.

I guess, my major problem is to convert the given results from CFX->fluent. I don't really know the fluent files, by I am not sure my .cas-file contains the results at all.
Do you know a procedure to obtain a fluent result file from a .res?

Regards!

mbeaudoin · May 2, 2013, 14:06

> Running cgnsToFoam converts the mesh, but the not the results themselvers.

Nope.

cgnsToFoam will convert the mesh AND the solution fields. This is why we wrote this utility in the first place...

cgnsToFoam -help

Martin

Quote:

Originally Posted by astein

Dear Foamers,

do you know any option to transform results (e.g. from CFX, CGNS, Tecplot) to the OpenFOAM format?
I'd like to postprocess some results with OpenFOAM tools, however I could not find a way to transform the results.

Running cgnsToFoam converts the mesh, but the not the results themselvers.

Any help is welcome, thanks a lot in advance!

astein · May 3, 2013, 04:54

Martin - thanks for that small but important hint :-)

The tool however ignores some of the (scalar) quantities I'd like to take over, because it doesn't know them. I couldn't find an option to convert the quantites anyway - did I overlook such an option? The alternative is to dig in the source code an add addtional quantites, right? Or do you even have a special version for this issue?

Regards & thanks a lot!

mbeaudoin · May 3, 2013, 13:25

> The tool however ignores some of the (scalar) quantities I'd like to take over, because it doesn't know them

The tool has no "knowledge" of specific fields. No quantity (scalar) names are hardcoded either.

cgnsToFoam just scans for solutions stored in the CGNS file, and convert them to OpenFOAM.

Just make sure your CGNS solutions are stored at the nodes (vertex) of the mesh, and not at the face centers or cell centers. You might have to tweak the configuration of your CGNS exporter for that.

Martin

Quote:

Originally Posted by astein

Martin - thanks for that small but important hint :-)

The tool however ignores some of the (scalar) quantities I'd like to take over, because it doesn't know them. I couldn't find an option to convert the quantites anyway - did I overlook such an option? The alternative is to dig in the source code an add addtional quantites, right? Or do you even have a special version for this issue?

Regards & thanks a lot!

May 2, 2013, 11:25	Transforming results to OpenFOAM format	#1
astein New Member Join Date: Mar 2010 Posts: 27 Rep Power: 16	Dear Foamers, do you know any option to transform results (e.g. from CFX, CGNS, Tecplot) to the OpenFOAM format? I'd like to postprocess some results with OpenFOAM tools, however I could not find a way to transform the results. Running cgnsToFoam converts the mesh, but the not the results themselvers. Any help is welcome, thanks a lot in advance!

May 2, 2013, 11:37		#2
wyldckat Retired Super Moderator Bruno Santos Join Date: Mar 2009 Location: Lisbon, Portugal Posts: 10,981 Blog Entries: 45 Rep Power: 128	Greetings astein, Since that's rarely used, there are very few ways to convert results from other applications to OpenFOAM. The only one I know about is fluentDataToFoam and it's part of Extend's variant OpenFOAM 1.6-ext: http://www.cfd-online.com/Forums/ope...of2-1-1-a.html And don't forget that you already need to have the mesh ready on the OpenFOAM case, otherwise there is no mesh to place the results inside it... And the big question is: if you have Tecplot, why do you want to use OpenFOAM for post-processing data? Best regards, Bruno __________________ OpenFOAM: FAQ \| Getting started Forum: How to get help, to post code/output and forum guide Read this before sending me PM

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May 2, 2013, 12:13		#3
astein New Member Join Date: Mar 2010 Posts: 27 Rep Power: 16	Thanks for your fast answerand the hint to fluentDataToFoam! With "postprocessing", I meant stuff like doing further compuations on the mesh based on given results. I have those methods available in OpenFOAM, but would like to run them on CFX results. Regarding fluentDataToFoam, I just gave it a try: I imported the .res file in Fluent and saved as a .cas - is that correct? (I tried both, binary and ASCII) starting fluentDataToFoam in a correct Foam case with "fluentDataToFoam testcase2.cas" for the ASCII-dat, starts working, but stops with: ################################# --> FOAM FATAL IO ERROR: Attempt to get back from bad stream file: IStringStream.sourceFile at line 0. From function void Istream::getBack(token&) in file db/IOstreams/IOstreams/Istream.C at line 39. FOAM exiting ################################# Any hints for this problem or other ideas to transform the results?

May 2, 2013, 12:25		#4
wyldckat Retired Super Moderator Bruno Santos Join Date: Mar 2009 Location: Lisbon, Portugal Posts: 10,981 Blog Entries: 45 Rep Power: 128	I guess you didn't read carefully that whole thread... Check this post, which is referenced on the first thread I had mentioned: http://www.cfd-online.com/Forums/ope...tml#post412947 post #4

May 2, 2013, 12:40		#5
astein New Member Join Date: Mar 2010 Posts: 27 Rep Power: 16	Thanks again for your fast reply! I'm trying to use the utility in a working 1.6-ext, having fluentDataToFoam compiled correctly - therefore I wouldn't expect any problems on this side. I guess, my major problem is to convert the given results from CFX->fluent. I don't really know the fluent files, by I am not sure my .cas-file contains the results at all. Do you know a procedure to obtain a fluent result file from a .res? Regards!

May 3, 2013, 04:54		#7
astein New Member Join Date: Mar 2010 Posts: 27 Rep Power: 16	Martin - thanks for that small but important hint :-) The tool however ignores some of the (scalar) quantities I'd like to take over, because it doesn't know them. I couldn't find an option to convert the quantites anyway - did I overlook such an option? The alternative is to dig in the source code an add addtional quantites, right? Or do you even have a special version for this issue? Regards & thanks a lot!