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Doubt of stability, convergence and steady-state.

    • nep
      Subscriber

      Hello,

      I attachment the results that i have in a process steady-state . With this results (unchecked residual checks) the residuals appear stable and the temperatures appear that it looks like they are going to continue like this. My doubt is:

      With these results, can I consider that the model is correct?

      Can I consider that the process has stabilized and is stationary?

    • Nikhil N
      Ansys Employee
      Hello,

      Ansys employees are not allowed to download any attachments from here. Can you please post the screenshots in the comment section directly?

      Nikhil
    • nep
      Subscriber
      I'm sorry, i think i attach as image.
      The pictures were:
      Thank you

    • Rob
      Forum Moderator
      You had attached the images, we're having problems loading stuff on this side. I think IT are messing with things they shouldn't....
      The residuals aren't converged, but suggest the solution isn't changing much. However, as the monitors are still changing I wouldn't trust the results. Are you monitoring any other points, and velocity anywhere?
    • nep
      Subscriber
      My system was a steel plate to which solar radiation is incident. I have also simulated the heat transfer which is the second variable I'm interested in after the plate temperature, and it seems that the heat transfer is stable, I introduce image:
      Do you think my model would be correct?
      Maybe the temperature should stabilize horizontally as it's steady state, but on the other hand FLUENT does not stop radiating 887 w/m2 , so it would be logical that the temperature continues to increase as in the first graph I think...
      Could you help me please? to know if it's right.
      Thank you very much for your help
    • Rob
      Forum Moderator
      I think it's still converging - the lines look flat as they're not changing much. Give it another few hundred iterations and review then.
    • nep
      Subscriber
      In 1000 iterations, the form is the same, appears:
      Can I consider that the process has stabilized? and, if it's true, as the temperature depends of the iterations, How many iterations i select?
      Thank you very much

    • Rob
      Forum Moderator
      Until it stops changing. Have a look at the flow and temperature field to see what's going on.
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