Residuals in PimpleFoam
 

Hi all

I have a very basic question:
What is a typical residuals behaviour for a converging pimpleFoam solver?

I think my simulation converges (see attachment), since the final residuals of the simple-iterations continuously decrease.
However, the initial residuals of the PISO-algorithm remain at a high level...

Is this a typical behaviour?

Any experience on this is very welcome
Best, Triggin

Is indeed typical behavior.

The residual goes haywire on the final iteration because this one has no under-relaxation urf = 1. In a converging PIMPLE solver, you never make it to the final PISO step and exit while still in SIMPLE mode.

Just to add to the answer, here is a link which might also be helpful for you understanding the residuals

http://openfoamwiki.net/index.php/Op...hm_in_OpenFOAM