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MPI barrier inside OpenFoam

Posted March 1, 2018 at 06:34 by kindle

Pstream has two sub directories :
dummy and mpi

Quote:
Originally Posted by matteoL View Post
Hello,
when running in parallel, for some reasons I have some actions that have to be done only by the master core and I would like the other partitions to wait until the master has finished.
(I call those action doing:
If (Pstream::master()){ ...} )


I think the solution in a general c++ code using MPI would be to add a line like:
MPI_BARRIER(MPI_COMM_WORLD)
...
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Old

pressure eq. "converges" after few time steps

Posted December 1, 2017 at 06:05 by kindle

Have a thread about simplefoam convergence.

Quote:
Originally Posted by maddalena View Post
thank you, however:

corrected is extra, isn't it?

This will no improve the initial convergence, since the solver will stop when the relTol is 0.05. thus it will not run until 1E-12 but stop at 0.05. And pressure equation will be not converged smoothly, I guess. What are your experience on the subject? What do you mean with not efficient?

Somewhere else it has been suggested to use pressure
...
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Old

Controlling y+ values with snappyHexMesh?

Posted November 30, 2017 at 14:04 by kindle

This can be useful y+ control !

Quote:
Originally Posted by seaspray View Post
Pete,

It might have got easier in the more recent versions. In a nutshell, you mesh your volume with a suitable algorithm (tets or hexa i,j,k) and viscous layers are added as an "additional hypothesis" in the 3D algorithm settings. In there, you have the option of excluding some faces in your geometry, like inlet, outlet, but also areas where you don't care as much about flow modeling like in some multiphase flow computations.
...
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Old

write a field in OpenFOAM

Posted October 30, 2017 at 04:01 by kindle

This is a good thread on writing an object


Quote:
Originally Posted by sven82 View Post
hi,

I will write out a variable of my own turb. model,
but its doesn't work.
First of all I define a ScalarField in my Header,

volScalarField hybrid_;

for the next step I edit the code file with a new Object

hybrid_
(
IOobject
(
"hybrid_",
runTime_.timeName(),
...
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Old

I want to use the 'turbulentIn

Posted September 25, 2017 at 13:47 by kindle

BC need to pay atttention

Quote:
Originally Posted by chris1980 View Post
I want to use the 'turbulentInlet' boundary condition. As far as I can see the use only inputs a fluctuation scale but what about the integral length scale or other appropiate scales because the flucation scale alone do not define a turublent inlet.

Ok I know it is anyway no real turbulent inlet because there is no turbulence strcuture etc.

Additionally, I was wondering what I have to set for k and epsilon at this turbulent boundary
...
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