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OpenFOAM sample utility

Hello,

could anybody give me an hint how to use sample utility correctly for all time steps?

I only would like to sample Ux from the velocity field U.

sampleDict-file

Quote:

setFormat raw;

surfaceFormat vtk;

interpolationScheme cellPoint;

fields
(
Ux
);

sets
(
lineX1
{
type uniform;
axis z;
start (1 0.125 0.01);
end (1 0.125 0.02);
nPoints 30;
}

);

If I use sample utility the folder sets is created, but contains only one time directory 0 including demanded Ux data. Other time directories, including Ux, are missing.

The help menu offers the option -time <range>.

sample -time :0.1-1.5: (and similar versions) don't work.

Aylalisa

Greetings Aylalisa,

A few questions:

Which OpenFOAM version are you using?
Try running:

Code:

sample -latestTime

Did it work at least for the final time instance?

If you are using OpenFOAM 2.2.0 and the last time instance was not outputted either, then the problem might be related to this one: http://www.openfoam.org/mantisbt/view.php?id=813 - if this is the case, then you'll need to upgrade to OpenFOAM 2.2.x.

As for running for all time steps, I think is should be something like ("1.5" is the last time step):

Code:

sample -time :1.5

Or better yet:

Code:

sample -time 0:

Best regards,
Bruno

Hello Bruno,

sample util works well if I sample U for all time steps or a range of time steps. All your recommended commands are fine.
I am not able to extract only Ux of velocity field U.
I have tried Ux, U(x), UX, U(1) and U.component(1) but do not receive the required result.

OpenFOAM version 2.1.1

Do you know the solution for my problem?

Thanks a lot!

Best regards,
Lisa

Quote:

Originally Posted by wyldckat (Post 420480)

Greetings Aylalisa,

A few questions:

Which OpenFOAM version are you using?
Try running:

Code:

sample -latestTime

Did it work at least for the final time instance?

Code:

sample -time :1.5

Or better yet:

Code:

sample -time 0:

Best regards,
Bruno

You have to create your components of the velocity vector before running sample utility with this command:
foamCalc components U
This will create Ux, Uy, Uz folders in your time directories. After that you can run the sample utility

I have tried this on OpenFOAM7, but without sucess.

But I did it as bellow:
postProcess -func "components(U)"

Then, next step on tutorial is execute the comand "sample", but I received:

Command 'sample' not found, but can be installed with:

sudo apt install barcode

What I have to do?

Quick answer: sample was replaced with using function objects only, namely you are meant to do a similar command to postProcess, but for sampling. See the OpenFOAM 7 User Guide, sub-section 2.2.3: https://cfd.direct/openfoam/user-gui...#x6-470002.2.3