Steady State Natural Convection problem with PISO
 

hi , all I tried Steady State Natural Convection problem with PISO algorithms. But this warning occurs.. Who do know this warning, solution?

*** WARNING #043 *** MINIMUM RESIDUAL AT THE END, RETURNING NON-CONVERGED SOLUTION

RESU = 5.79205E-03 RESV = 4.46443E-03 RESW = 4.42205E-03 RESP = 5.27473E-01

REST = 1.21827E-04

*** WARNING #013 *** MAXIMUM SPECIFIED CORRECTOR STAGES 20 REACHED BEFORE CONVERGENCE CRITERION IS SATISFIED.

<<<<CONTINUITY EQUATION NOT CONVERGED>>>>

Re: Steady State Natural Convection problem with P
 

This may indicate that you have reached the steady state solution and PISO can not reduce the residuals any further?

Re: Steady State Natural Convection problem with P
 

Thanks Mr.john YL for your reply.... I want to know whether the warning affects my solution, and know the way to remove the warning.

Please post response.

Thank you!!!!!!!

Re: Steady State Natural Convection problem with P
 

Hallo Jerry!

I think your solution is NOT converged. You can try increasing the maximum number of PISO corrector stages to a higher number. And you should link star in double precision (that's always advisable with natural convection problems).

If you can't get a converged solution this way, then you should try a transient aproach, as most natural convection problems are not stationary.