Give the file the proper header for being used as TimeVaryingMappedFixedValue input
 

Hi Foamers,

In the file foamFileSurfaceWriter.C in "src/sampling/sampledSurface/writers/foamFile" , I can see the following line

which prints the sampled field, e.g. U as the output. I should sample velocity at the inlet BC at each time step, during a very long time. In this way, I would have a huge number of time folders, yet lacking the OpenFOAM header (just vector values and coordinates).

I want to feed these time series into another simulation as boundary condition using TimeVaryingMappedFixedValue BC. But this BC demands for input files with headers.

Unfortunately, it is not possible to add header to each file manually, because the number is huge!
I have tried something like the following code to add the proper header, but without success:

the following error appears when compiling:

Is there any way to solve this problem and adding the proper header to the files generated through the sampling??

Thanks,
Syavash

Anyone who might be interested?? This is a real problem for me since I need inlet velocity at each time step to be saved and used as boundary condition for another LES simulation!
I also checked sample utility but it similarly only saves values and generates no header!

TimeVaryingMappedFixedValue demands a header for velocity like this:

Code:

---

/*--------------------------------*- C++ -*----------------------------------*\
| =========                |                                                |
| \\      /  F ield        | OpenFOAM: The Open Source CFD Toolbox          |
|  \\    /  O peration    | Version:  2.3.1                                |
|  \\  /    A nd          | Web:      www.OpenFOAM.org                      |
|    \\/    M anipulation  |                                                |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version    2.0;
    format      ascii;
    class      vectorAverageField;
    object      values;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

---

How can I generate a header like one in above for my sampled inlet boundary??

Thanks,
Syavash

Anyone who might be interested?? This is a real problem for me since I need inlet velocity at each time step to be saved and used as boundary condition for another LES simulation!
I also checked sample utility but it similarly only saves values and generates no header!

TimeVaryingMappedFixedValue demands a header for velocity like this:

[CODE]

Code:

---

/*--------------------------------*- C++ -*----------------------------------*\
| =========                |                                                |
| \\      /  F ield        | OpenFOAM: The Open Source CFD Toolbox          |
|  \\    /  O peration    | Version:  2.3.1                                |
|  \\  /    A nd          | Web:      www.OpenFOAM.org                      |
|    \\/    M anipulation  |                                                |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version    2.0;
    format      ascii;
    class      vectorAverageField;
    object      values;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

---

How can I generate a header like one in above for my sampled inlet boundary??

Thanks,
Syavash

No one can help me??!:(
I am really stuck in this!

Dear Syavash,

I also met similar problem before, and I have written a matlab script to add the head to the sampled file.

Suppose your sampleDict reads like this:
After sample you will have many timestep folders under the directory: 'xx/postProcessing/surfaces/' and within each timestep folder you have the sampled surface 'mySampleSurface/'.

Here is the matlab script that I used to add the header and to move the required files directly under the timestep folder.

After this you can copy the folder ''mySampleSurface" to the ''constant/boundaryData" of your new case.

Hope this helps.

Best,
Likun

Dear Likun,

Thank you for sharing your solution. :)
Unfortunately, Matlab could not recognize 'cp' and 'rm' commands in your scrip! But I am aware that this is an issue with the version installed on my PC!
I could find a workaround. I could make the solver (pimpleFoam) to write the sampled plane (inlet bc) at each time steps. In this way, OpenFoam automatically generates a header with class vectorField just like the following:

Then, I replaced keyword vectorField with vectorAverageField and '960'with '(0 0 0) 960', (960 is the number of faces in inlet bc) respectively using the following commands in linux terminal:
These command find and replace the desired keywords. The option '-i' allows the command 'sed' to be executed as 'in place', i.e. find a file in a folder, open and replace the desired word, save and then close to continue searching for another file.

Regards,
Syavash

Hi

If you got this to work, do you think it would be possible to run both simulations simultaneously?

So the 'inlet' BC reads the 'outlet' BC while the solver is running?

The IOobject class has the member functions writeHeader and readHeader that write the appropriate headers to streams. Since files are abstracted as streams in C++, we can use the IOobject class to write a header to a file. Here is how the application looks like:

When executed, it will write the header to the output stream, using the global messageStream Info object, and also to the output file stream (file), named "myFile".

If you want to change the parameters of the header, change the IOobject constructor arguments.

Ali,

I am not really sure. The above-mentioned solution makes me able to perform a precursor simulation before doing the primary simulation.Adding that my computational resource does not allow me to have two simultaneous simulations!

Besides, I think it is the most appropriate solution for me to save data on a plane in advance, since I would be able to implement the data for as many simulations as I want to perform.

Regards

Thanks Syavash

I'm planning on trying something like that, but it looks like it's going to be difficult!

regards