[jormollo]

Hello!
I am using OF 1812 with Ubuntu 18.04 and it works perfectly. However, I am trying to measure forces on a patch with a writeInterval equals to 0.05 seconds but the output of the force register is given for each TimeStep. How could I fix it?

Below I attach the code of my ControlDict.

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  1.3                                   |
|   \\  /    A nd           | Web:      http://www.openfoam.org               |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version         2.0;
    format          ascii;
    location        "system";
    class           dictionary;
    object          controlDict;
}

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

application interFoam;

startFrom       latestTime;

startTime       0;

stopAt          endTime;

endTime         20;

deltaT          0.001;

writeControl    adjustableRunTime;

writeInterval   0.1;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression on;

timeFormat      general;

timePrecision   6;

runTimeModifiable yes;

adjustTimeStep  yes;

maxCo           0.45;

maxAlphaCo      0.45;

maxDeltaT       0.05;

libs (
         "libOpenFOAM.so"
     );

functions
{


// Forces on crown wall
    forceProbeHor
    {
        type            forces;
        libs            ( "libforces.so" );
        writeFields     no;
        writeControl    adjustableRunTime;
        writeInterval   0.05;
        patches         ( Espaldonfrontal );
        log             false;
        CofR            (18.45 0.02 0.80); // center of rotation
//        rhoInf          1000;

    };

    forceProbeVer
    {
        type            forces;
        libs            ( "libforces.so" );
        writeFields     no;
        writeControl    adjustableRunTime;
        writeInterval   0.05;
        patches         ( Espaldonbase );
        log             false;
        CofR            (18.45 0.02 0.80); // center of rotation
//        rhoInf          1000;

    };
}

[Eldrael]

Hello jormollo:

I do not think that you can order OpenFOAM to just write the postprocessing data each 0.05 seconds in a "de-coupled way" of your timestep.

I think that your best alternative is to create a script to read the data and postprocess on your own. Interpolation should do.

There are many alternatives, but you can just load the file to a pandas database in python launching the next script from the case folder:

import pandas as pd
import numpy as np
from pathlib import Path

#Get all the forces files.
thisCase=Path('.')
allForcesFiles=[x for x in thisCase.glob('**/*forces.dat')]
allForcesAsDataframes=[]
header=['Time', 'Force pressure x','Force pressure y','Force pressure z', 'Force viscous x','Force viscous y','Force viscous z','Force porous x','Force porous y','Force porous z', 'Torque pressure x','Torque pressure y','Torque pressure z', 'Torque viscous x','Torque viscous y','Torque viscous z','Torque porous x','Torque porous y','Torque porous z']

#If there is more than one forces file the addressing of forces files and their names is in allForcesFiles.
for file in allForcesFiles:
    toDrop=[]
    thisDatabase=pd.read_csv(file, header=None, skiprows=range(3), delimiter="\s+|\(+|\)+",engine='python') 
    for column in thisDatabase: 
          if thisDatabase[column].isnull().values.any(): 
              toDrop.append(column)
    thisDatabase=thisDatabase.drop(toDrop,axis=1)
    thisDatabase.columns=header
    allForcesAsDataframes.append(thisDatabase)

Mind that the script might not be the most optimized way but it will work as expected. My recomendation is to load it with Spyder included in Anaconda.

Postprocessing aftwerards should be straightforward.

[jormollo]

Originally Posted by Eldrael

Hello jormollo:

I do not think that you can order OpenFOAM to just write the postprocessing data each 0.05 seconds in a "de-coupled way" of your timestep.

I think that your best alternative is to create a script to read the data and postprocess on your own. Interpolation should do.

There are many alternatives, but you can just load the file to a pandas database in python launching the next script from the case folder:

import pandas as pd
import numpy as np
from pathlib import Path

#Get all the forces files.
thisCase=Path('.')
allForcesFiles=[x for x in thisCase.glob('**/*forces.dat')]
allForcesAsDataframes=[]
header=['Time', 'Force pressure x','Force pressure y','Force pressure z', 'Force viscous x','Force viscous y','Force viscous z','Force porous x','Force porous y','Force porous z', 'Torque pressure x','Torque pressure y','Torque pressure z', 'Torque viscous x','Torque viscous y','Torque viscous z','Torque porous x','Torque porous y','Torque porous z']

#If there is more than one forces file the addressing of forces files and their names is in allForcesFiles.
for file in allForcesFiles:
    toDrop=[]
    thisDatabase=pd.read_csv(file, header=None, skiprows=range(3), delimiter="\s+|\(+|\)+",engine='python') 
    for column in thisDatabase: 
          if thisDatabase[column].isnull().values.any(): 
              toDrop.append(column)
    thisDatabase=thisDatabase.drop(toDrop,axis=1)
    thisDatabase.columns=header
    allForcesAsDataframes.append(thisDatabase)

Mind that the script might not be the most optimized way but it will work as expected. My recomendation is to load it with Spyder included in Anaconda.

Postprocessing aftwerards should be straightforward.

Thank you for your recommendation. I achieved to do it with the pressure sampling for example using a "type probes" in the controlDict....If it is not possible I will filter the signal after recording it. Thanks!