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Sample different fields in different sets and surfaces

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Old   April 1, 2016, 08:10
Question Sample different fields in different sets and surfaces
  #1
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Ion
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Is it possible to sample different fields for different sets and surfaces?

If the pressure field is relevant just in some patch and temperature in other one, is there a way to obtain both without having to call the sample utility twice?

The keys here are:
  • avoiding unnecessary files creation
  • loading the case in memory just once
Thanks in advance!
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Old   April 4, 2016, 06:26
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AFAIK this is not possible. You could create multiple sampleDict files and maybe make it automatic by writing a small script.
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Old   April 4, 2016, 09:33
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Quote:
Originally Posted by Bazinga View Post
AFAIK this is not possible. You could create multiple sampleDict files and maybe make it automatic by writing a small script.
Hi Bazinga!

First of all, thanks for replying

Making several calls to sample would require loading the case several times, and that's precisely what I'm trying to avoid.

Let's see if someone comes with a different solution in which the case gets loaded and then all samples are performed.

Cheers!
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Old   November 2, 2017, 12:17
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You can do that with function objects in system/controlDict.
Not sure that helps, because you have to decide in advance what you want to get sampled, or at least changes only apply to future times.

Here's an example:
Code:
functions
(
    someSampleSets
    {
        type                   sets;
        functionObjectLibs     ("libsampling.so");
        setFormat              raw;
        interpolationScheme    cellPoint;
        outputControl          outputTime;
        sets
        (
            someSet
            {
                type        uniform;
                axis        x;
                start       (0 0 0);
                end         (1  1 1);
                nPoints     100;
            }
            someOtherSet
            {
                type        uniform;
                axis        y;
                start       (1 0 0);
                end         (0  1 1);
                nPoints     100;
            }

        );
        fields
        (
            U p
        );
    }
    someSurfaces
    {
        type                    surfaces;
        functionObjectLibs      ("libsampling.so");
        surfaceFormat           raw;
        interpolationScheme     cellPoint;
        outputControl           outputTime;
        fields
        (
            alpha
        );
        surfaces
        (
            someSurface
            {
                type        isoSurface;
                isoField    alpha;
                isoValue    0.5;
                interpolate true;
            }
        );
    }
);
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Old   December 18, 2020, 05:38
Question How do you run sampling with this setting?
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Quote:
Originally Posted by RL-S View Post
You can do that with function objects in system/controlDict.
Not sure that helps, because you have to decide in advance what you want to get sampled, or at least changes only apply to future times.

Here's an example:
Code:
functions
(
    someSampleSets
    {
        type                   sets;
        functionObjectLibs     ("libsampling.so");
        setFormat              raw;
        interpolationScheme    cellPoint;
        outputControl          outputTime;
        sets
        (
            someSet
            {
                type        uniform;
                axis        x;
                start       (0 0 0);
                end         (1  1 1);
                nPoints     100;
            }
            someOtherSet
            {
                type        uniform;
                axis        y;
                start       (1 0 0);
                end         (0  1 1);
                nPoints     100;
            }

        );
        fields
        (
            U p
        );
    }
    someSurfaces
    {
        type                    surfaces;
        functionObjectLibs      ("libsampling.so");
        surfaceFormat           raw;
        interpolationScheme     cellPoint;
        outputControl           outputTime;
        fields
        (
            alpha
        );
        surfaces
        (
            someSurface
            {
                type        isoSurface;
                isoField    alpha;
                isoValue    0.5;
                interpolate true;
            }
        );
    }
);
Hi,

the thread is a bit old but I am trying to the exact same thing. I tried the code in OF version 7 but I am not sure how I am supposed to run singleGraph utiliy. OF doesn't create sets of samples when I run my case with the "postprocess -func singleGraph" in terminal. My controlDict File is below. What am I doing wrong here?


Code:
/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  7
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "system";
    object      controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

application     interFoam

startFrom       startTime;

startTime       0;

stopAt          endTime;

endTime         10;

deltaT          2e-4;

writeControl    runTime;

writeInterval   2e-2;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression off;

timeFormat      general;

timePrecision   6;

runTimeModifiable false;

adjustTimeStep  yes;

maxCo 0.4;
maxAlphaCo      0.4;

functions
{
Co
{
    // Mandatory entries (unmodifiable)
    type            CourantNo;
    libs            ("libfieldFunctionObjects.so");

    // Optional entries (runtime modifiable)
    rho             rho;

    // Optional (inherited) entries
    field           <phi>;
    result          <fieldResult>;
    region          region0;
    enabled         true;
    log             true;
    timeStart       0;
    timeEnd         10;
    executeControl  adjustableRunTime;
    executeInterval 2e-2;
    writeControl    adjustableRunTime;
    writeInterval   2e-2;
 }
singleGraph
{

 someSampleSets
    {
        type                   sets;
        functionObjectLibs     ("libsampling.so");
        setFormat              raw;
        interpolationScheme    cellPoint;
        outputControl          outputTime;
        sets
        (
           line0
            {
                type        lineCell;
                axis        y;
                start       (0.02 -0.04 0);
                end         (0.02 0.04 0);
            }
            line1
            {
                type        lineCell;
                axis        y;
                start       (0.045 -0.04 0);
                end         (0.045 0.04 0);
            }

        );
        fields
        (U p k omega nut Co);
    }
}

#includeFunc  probes;
}
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