Problem in simulation
 

Hi Foamers,

I am starting to feel desperate. I am simulating the flow of complex fluids in OpenFoam, where extra tensions are significant. In the momentum balance equations there is an extra divergence term of the extra tension. Right now, I am doing the simulations imposing in the fvSchemes upwind for the advection terms, but the divergence of extra tension is discretized using Gauss Linear Corrected.

I noticed that the behaviour is better, but, when the extra tension is large, ths simulation blows suddenly. It starts converging, and out of the blue the velocity and pressure values.

What I can do to avoid this? Some possibilities I am thinking of are:

- instead of starting with a flow field with zero velocity use a flow field that has converged and then change the parameters.
- use other linear solvers or reduce the total errors.
- try other relaxation factors.

Has anybody other ideas.

Regards,

Titio