CFD Online Discussion Forums - Convective outlet boundary condition for Unsteady flows

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Well,
Well I tried waveTransmissive BC. I have somewhat similar case which Daniel has talked about in some previous posts (O mesh for a simulation over a cylinder). waveTransmmissive BC seems to work for me with LES but I don't know how to justify it. I don't completely understand the mathematics involved. In OF documentation it says that it is supposed to work with involving shocks (specially supersonic). If you see the pitzDaily tutorial for LES in rhoPimpleFoam it also uses the waveTransmissive BC.
I don't understand that under which circumstances this waveTransmissive BC would be more appropriate or attractive for a simulation.
I don't need the whole explanation, but some pointer in terms of physics (not mathematics) could help me a lot. :D
Regards,
Awais

hi.
any body know convective outlet B.C work with openfoam 1.6 ext?

thanks

this B.C compile with no error on openfoam 1.6.ext. work fine for me

Hi Foamers,

Can anyone post a new version of the convective outlet b.c. again (works in in 1.6 or 1.7+++)? It seems the previous links are out of date and cannot be downloaded. Thanks very much.

Quote:

Originally Posted by tfuwa (Post 382456)

Hi Foamers,

Can anyone post a new version of the convective outlet b.c. again (works in in 1.6 or 1.7+++)? It seems the previous links are out of date and cannot be downloaded. Thanks very much.

to summarize this long post:
you can download the original Takuya code from the post #36
just rename the file to .tar after download & extract it

askjak also changed this code for OF 1.5 ++ that you can download from the post #77 including pitzDaily test case
All the download links work fine for me

Quote:

Originally Posted by 7islands (Post 267628)

Hi Pascal,
I can point you to where you can download a version that compiles with 1.6.x (or even 1.7), but as you state that you are learning C++, I'd leave the fix to you as it'll be a good exercise :)

Nevertheless if you are looking for a prompt solution, search OFWiki for convectiveOutlet.

Takuya

Dear Takuya 7islands

Thanks for sharing your code
I have seen the page: potentialWaveFoam that you created in the folllowing url:
http://openfoamwiki.net/index.php/Co...entialWaveFoam
which has
convectiveOutlet-YYYYMMDD/ a convection BC code
inside it
I have some questions:

1) is it the same code that you have posted in here?
because it requires username&password for downloading it from:
https://www.openacoustics.org/svn-re...entialWaveFoam
can you attach it here in the foroum?

2)I have read all the posts regarding OpenFOAM advective outlet B.C. in this thread and other posts but I still have some doubts:

2-1) can we use advective outlet B.C. instead of convective outlet B.C. for incompressible flows?
2-2) is it reliable?
2-3) is there any example in the OpenFoam tutorial or other sources that can help us adjusting the related parameters for using this B.C.?

Best Regards

Hi All,

I am a noob in Openfoam. Could any of you explain me how this convective boundary condition code exactly works? I tried going through it a number of times, but I could not figure out where does the d/dt term come from and where does the gradient term comes from?

Thanks and regards,

Hrushikesh

in which situations this BC(Convective BC) is applicable?

and can it be used for OpenCFD Ltd version too?

boundary condition for Blade-plane configuration

Hello all,
I am new in openfoam.
I would like to implement boundary condition for Blade-plane configuration in electrostatic problem.
I want to implement potential value V= sin(2*π*f*t) at inlet.
Can anyone help me for this problem.

Thank you.