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-   -   PISO in FLUENT vs. OpenFOAM (

Industrial_CFD February 4, 2013 21:40

Hi guys,

I am trying to get an LES case set up in openfoam, and I have been trouble shooting with FLUENT. FLUENT iterates PISO until the specified max iterations are reached ( or until convergence). Is there anyway to run pisoFOAM like this? Would this implementation be pimpleFoam?


Chris Lucas February 5, 2013 10:43


have a look at pimpleFoam. However, as I know, pimpleFoam doesn't check if the solution is converged. You have to programm it (a guess 10 lines of code) yourself.

Kind Regards,

Industrial_CFD February 7, 2013 11:14

What is really amazing is that OpenFOAM won't converge compared to the same settings in FLUENT (I think anyway). FLUENT handles the case easily, whereas OpenFOAM cannot converge the pressure term.
It is really strange. I'm starting to wonder if it is a bug or something.

Chris Lucas February 11, 2013 06:43


the reason for the different results is not a bug. Some of the internal program structure is different.

Fluent has probably internal limiter that help to converge the solution (using numerical diffusion) and openfoam doesn't.

What are you trying to simulate. What schemes do you use. What OF version? Is time accuracy important?

Kind Regards,

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