How can I check imbalance?
 

Hi all.

I'm simulating about fan.
But result is not reasonable, and I was advised to check imbalance.
He said that I can check imbalance in solver window, i.e. CFX-Solver manager like RMS, Turbulence, and so on.
I searched several manuals, but I couldn't find.

I'm nearly new to CFX, and actually I didn't understand even what imbalance means

Any help will be highly appreciated.
Thanks in advance!

Hi

When the solver run is finished, the final values for imbalance are reported in the reports shown at the end.
But if you wish to monitor them during thee run, you should add a new monitor for that. Right Click on the upper tabs of the workspace (Like momentum and mass tab) and click on the "New monitor". Ok in the appearing windows, then in the next windows check the boxes for the equations which you want to monitor their imbalance. and click apply. I suggest you to change the monitor axis type to the log scale in the middle tab, cuz you can observe their variation better this way.
Experts should comment on the physical meaning of the imbalance, but as far as I know imbalance means the net difference between boundaries of a domain for each variable. my experience is, an imbalance of 0.1 or less might denote a converged solution.
Best
Ali

Sorry for my late answer.

Thank you very much. I have checked imbalance near fan.

I'm simulating two fans.
Front fan is OK, but back fan is the problem.
Imbalance of back fan is oscillating in the range of +- 5%.

Do you know about this phenomenon??
I totally don't know what I should do..TAT

Any help will be highly appreciated.
Thank you.

Run your simulation for longer to allow it to converge tighter. If it is not converging then refer to this FAQ: http://www.cfd-online.com/Wiki/Ansys...gence_criteria