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melek December 25, 2013 21:41

pressure iteration didnt converge
1 Attachment(s)
how can I edit this error? what is that mean?

Solver Messages: pressure iteration did not converge in itmax= 100 iterations
at time= 1.03537E-02 cycle= 90 iter= 100 nocon= 0
epsi= 4.083E-01 maximum residual= 5.539E-01 at i= 124 j= 2 k= 70 block= 5
convective flux exceeded stability limit
at t= 3.2759E-02 cycle= 306 iter= 5 delt= 3.4220E-05 mesh block 5
restarting cycle with smaller time step
maximum failure ratio = 2.95606E+00 is in z-coordinate direction
at cell ( 233, 2, 215) mesh block 5

mo.sharifabadi December 30, 2013 04:30

Dear Melek
The solver, solve 100 times an iteration, if the stop criteria accepted then go to next iteration, but if it unaccepted so stop the solving. So, no way to get the accurate simulation results.

M. R. sharifabadi

melek January 11, 2014 13:49

Thank you Sharifabadi. so do you have any idea how can I correct the mistake... I tried to increase GMPRES number and decrease messh sell sizes. However the simulation runned with 2 gb and again took this message. pressure iteration didnt converse itmax =100

mo.sharifabadi January 12, 2014 05:07

As far as I know, there is no way to take away from this problems, restart your simulation from first ( call STL files ) and do simulation again may you haven't problem.

Don't hesitate if you have any question.
this is my email address:

johnsonw March 7, 2014 02:50

Have you corrected you problem? i am stuck in such a situaiton too

macsim March 26, 2014 11:13

Do you have different mesh blocks in your model ?

It can be due to connection problems between mesh blocks (or bad cell size ratio).

johnsonw March 26, 2014 21:59


Originally Posted by macsim (Post 482222)
Do you have different mesh blocks in your model ?

It can be due to connection problems between mesh blocks (or bad cell size ratio).

I didn't add any mesh plane to the mesh block,just let mesh generator do the job.

macsim March 27, 2014 07:09

If you have thin thickness, it could be interesting to add mesh planes.

Usually, a list of messages as your comes from bad mesh conditions. When you analyze results, geometry visualization is good ?

melek March 28, 2014 11:15

Thank you for answers, mesh and geo was crossed I thınk but only I wrote relaxatıon factor = 0,5 and downed tıme step all problems are over

melek March 28, 2014 11:18

And mesh was strong I thınk chanced mesh desıgn

melek March 28, 2014 11:24

thank you for answers

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