[trailer]

Hello to all,


I am using OpenFoam 2012 and would like to plot the residuals of pressure and velocity during the execution of the simulation.


I am using the functionObject solverInfo as:

    solverInfo
    {
        type            solverInfo;
        libs            ("libutilityFunctionObjects.so");
        fields          (U p);
        writeResidualFields no;
        executeControl      timeStep;
        executeInterval     10;
    }

However, this outputs a lot of information... And I only require the value of the initial residual of p and U.



Afterwards, when I plot the residuals with foamMonitor the plot gets very crowded.



Is it possible to restrict the information output from the functionObject to just the initial residuals? Or alternatively to just plot the initial residuals of variables with foamMonitor?

[klausb]

There's also a very powerful python tool called "pyFoam" for that purpose.

It includes utilities like pyFoamRunner and pyFoamPlotWatcher which are relevant for the purpose you mention. You should also have a look at youtube e.g. "How to plot residuals in OpenFOAM: functionObject and pyFoam utilities" which goes into custom configuration of residual plots to some extend.

[trailer]

Originally Posted by klausb

There's also a very powerful python tool called "pyFoam" for that purpose.

It includes utilities like pyFoamRunner and pyFoamPlotWatcher which are relevant for the purpose you mention. You should also have a look at youtube e.g. "How to plot residuals in OpenFOAM: functionObject and pyFoam utilities" which goes into custom configuration of residual plots to some extend.

Hi,


Thanks for the reply.


I ended up using solverInfo functionObject but filtered the data with an executable script. The code bellow will look for _initial termination and plot only the variables with it.

 filename=$1
 gnuplot -persist <<-EOFMarker
     set datafile commentschars "" 

    set datafile separator tab
     set key noenhanced 

    set logscale y 

    set title 'Residuals'  

    set ylabel 'Residual'
    set xlabel 'Iteration'
     myHeaders = system("head $filename | grep -o '[^ ]*_initial[^ ]*'")
      plot for [i=1:words(myHeaders)] '$filename' u "# Time":word(myHeaders,i) skip 1 w l ti columnheader  

 EOFMarker

Usage of the script:


Create a file called foamPlot. Paste the code inside.
Make it an executable file with:

chmod +x foamPlot

Navigate to the folder with the solverInfo.dat file

Use it with:

foamPlot solverInfo.dat

[HPE]

Would you mind to comment on what could be improved/what should be done item by item in the "solverInfo" function object, so that the user might have lesser pain?

[trailer]

Originally Posted by HPE

Would you mind to comment on what could be improved/what should be done item by item in the "solverInfo" function object, so that the user might have lesser pain?

Hi,

Sure! Just put a switch to just filter the initial residuals instead of "everything". This would be a similar behavior to what OpenFOAM foundation has: https://github.com/OpenFOAM/OpenFOAM...ties/residuals


This way, you could just plot the residuals with :

foamMonitor -l solverInfo.dat

[HPE]

hmm interesting. The "solverInfo" FO is the updated version of the "residuals"; in fact, it was renamed. I have put it at the end of my to-do list (which is longer than Gandalf's hair atm).