difference between U().boundaryField()[patchI] and U().boundaryField()[patchI].patchI

cctv · September 7, 2013, 08:02

Hi:
I am wondering if any one know the difference between U().boundaryField()[patchI] and U().boundaryField()[patchI].patchInternalField()? and the difference between aMesh().faceAreaNormals() and aMesh().faceAreaNormals().internalField() in openfoam-1.6-ext.Thanks

jherb · September 9, 2013, 08:27

your first version gives you the values on the patch surface whereas the second version returns the values in the cells next to the surface.

cctv · September 10, 2013, 07:43

Quote:

Originally Posted by jherb

your first version gives you the values on the patch surface whereas the second version returns the values in the cells next to the surface.

Thank you for your reply. I have made a comparison with the internalfield and cell centre field. and I found though these two value are very close, they are not the same. So I think there must be something differences between them. In addition, for famesh, do they have cells next to them?

jherb · September 10, 2013, 16:06

What values/fields have you compared? What happens if you compare the cell center coordinates (.C(), http://www.cfd-online.com/Forums/ope...l-centers.html )?

Quote:

Originally Posted by cctv

Thank you for your reply. I have made a comparison with the internalfield and cell centre field. and I found though these two value are very close, they are not the same. So I think there must be something differences between them. In addition, for famesh, do they have cells next to them?

cctv · September 10, 2013, 16:16

Quote:

Originally Posted by jherb

What values/fields have you compared? What happens if you compare the cell center coordinates (.C(), http://www.cfd-online.com/Forums/ope...l-centers.html )?

I compared the U().boundaryField()[patchI].patchInternalField and U file in corresponding time output folder, and find they are not exactly the same.

jherb · September 10, 2013, 17:44

When do you print out the values of the patchInternalField. Are you sure there is no call to the solver or some boundary.correct()? Otherwise the internal values would be modified before stored in the output files.

cctv · September 10, 2013, 19:22

Quote:

Originally Posted by jherb

When do you print out the values of the patchInternalField. Are you sure there is no call to the solver or some boundary.correct()? Otherwise the internal values would be modified before stored in the output files.

Yes, I think you are right. Thank you very much.

September 7, 2013, 08:02	difference between U().boundaryField()[patchI] and U().boundaryField()[patchI].patchI	#1
cctv Member Yu CAO Join Date: May 2013 Posts: 76 Rep Power: 13	Hi: I am wondering if any one know the difference between U().boundaryField()[patchI] and U().boundaryField()[patchI].patchInternalField()? and the difference between aMesh().faceAreaNormals() and aMesh().faceAreaNormals().internalField() in openfoam-1.6-ext.Thanks

September 9, 2013, 08:27		#2
jherb Senior Member Joachim Herb Join Date: Sep 2010 Posts: 650 Rep Power: 22	your first version gives you the values on the patch surface whereas the second version returns the values in the cells next to the surface. luiscardona, randolph, Luttappy and 2 others like this.

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September 10, 2013, 17:44		#6
jherb Senior Member Joachim Herb Join Date: Sep 2010 Posts: 650 Rep Power: 22	When do you print out the values of the patchInternalField. Are you sure there is no call to the solver or some boundary.correct()? Otherwise the internal values would be modified before stored in the output files.