[sasanghomi]

Hi every body,

I have a question about relaxation factor :
sonicTurbDymEngineFoam is a transient solver for compressible flow with mesh motion.(OP-1.6-ext)
It uses PISO algoritm for solving equations.when I use relaxation factor in a case with this solver I get correct result.Do you think using of relaxation factor in PISO algorithm is wrong??? why???
In a header file of the source code of this solver I saw this code :

UEqn.relax();

thanks,
Sasan.

[wyldckat]

In order to give a bump to this thread, here's what I answered Sasan the other day, through private messaging:

Originally Posted by wyldckat

Hi Sasan,

I don't know much about this. All I know is:

1. Both PISO and SIMPLE can be used for transient simulations.
2. PISO algorithm is described here: http://openfoamwiki.net/index.php/Th...hm_in_OpenFOAM
3. SIMPLE algorithm is described here:http://openfoamwiki.net/index.php/Th...hm_in_OpenFOAM
4. Then there is PIMPLE, which is a mix of PISO+SIMPLE... and I quote:
   

Therefore, the relaxation factors you're talking about may depend on whether you're using PISO or PIMPLE.


You might have gotten a better answer if you had asked in the public forum...

Best regards,
Bruno