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-   -   fvSchemes in FOAM extend 3.1 (https://www.cfd-online.com/Forums/openfoam-solving/145807-fvschemes-foam-extend-3-1-a.html)

Shenan December 12, 2014 11:34

fvSchemes in FOAM extend 3.1
 
I tried running the LRR turbulence model in OF 2.2.1 but ran into difficulty with time step continuity errors blowing up. I tightened the pressure convergence criteria but still it blew up; so I thought I'd give FOAM 3.1 a try.

I thought most things would be portable but some of the fvSchemes that I was using in OF are not recognised by FOAM. For instance, in OF I had:

Code:

div(phi,U)      bounded Gauss linearUpwindV grad(U);
In FOAM,
Code:

bounded
was not recognised; so I removed it and then
Code:

grad(U)
was not recognised. The problem is that I don't know what to replace it with.

Is there a "dictionary" to "translate" between OF and FOAM?

Tushar@cfd December 16, 2014 23:26

Quote:

Originally Posted by Shenan (Post 523675)
I tried running the LRR turbulence model in OF 2.2.1 but ran into difficulty with time step continuity errors blowing up. I tightened the pressure convergence criteria but still it blew up; so I thought I'd give FOAM 3.1 a try.

I thought most things would be portable but some of the fvSchemes that I was using in OF are not recognised by FOAM. For instance, in OF I had:

Code:

div(phi,U)      bounded Gauss linearUpwindV grad(U);
In FOAM,
Code:

bounded
was not recognised; so I removed it and then
Code:

grad(U)
was not recognised. The problem is that I don't know what to replace it with.

Is there a "dictionary" to "translate" between OF and FOAM?

Hello Shenan,

If I am correct then the "bounded" term was included in OpenFOAM from OF ver. 2.2 onwards. This term will be beneficial if you are running steady-state solver. It will bound your solution and help achieve better convergence.

-
Best Regards!

hjasak December 17, 2014 11:39

Try

Gauss linearUpwindV Gauss linear;

Shenan December 22, 2014 09:45

Thanks for the tip, Hrv. Unfortunately, the solver did not converge.

The time step continuity errors (sum local) went from 0.01 in the second iteration to 2e+05 in the third.

Of the other parameters, only bounding epsilon (max) showed signs of divergence: from 470 in the second iteration to 2e+08 in the third.

I will have a look at this again after Xmas. It might not be a problem with fvSchemes.


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