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Kushagra July 4, 2008 18:04

Monitor point values in a steady state simulation
 
A steady state simulation with Blend factor =0.9 has reached the situation where RMS residual levels are 10^-6 and global imbalances are near 1% or 2%.

BUT the monitor point values such as Volume fraction at the outlets are still changing (slightly) with iterations.

Should I consider the simulation reached steady state? In short, my question is as follows:

"Should the monitor point values NOT change with iterations in steady state if the steady state has been obtained?"

Thanks, Kushagra

johnny July 6, 2008 18:49

Re: Monitor point values in a steady state simulat
 
I would say that you want low residuals, low imbalance, and small fluctuations in any monitor points to consider your solution to be converged. The fluctuations in a monitor point will give you some indication as to the accuracy of the final solution.

If you monitor point is fluctuating, maybe you have a condition that is unsteady, and you may want to consider running it transient to get better accuracy or model the flow properly.

Rogerio Fernandes Brito July 13, 2008 20:03

Re: Monitor point values in a steady state simulat
 
I am simulating a case in a steady state and the temperature and the velocity are changing. You can decrease the target error to see if the results are reaching the steady state


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