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-   -   questions to the plot of pyFoamPlotWatcher (https://www.cfd-online.com/Forums/openfoam-post-processing/88009-questions-plot-pyfoamplotwatcher.html)

tH3f0rC3 May 5, 2011 09:44

questions to the plot of pyFoamPlotWatcher
 
1 Attachment(s)
Hi,

I have simulated a steady state flow of air with no heat transfer with simpleFoam. Because it is my first time using the pyFoamPlotWatcher I have some questions:

- I think the epsilon_max is very strange. Can I plot the epsilon values to see where the high epsilon value appears in the geometry?
- What is meant with CUmultative and Global?
- Is it fine that the residues begin to jitter when they shrink? Is this due to the logarithmic scale?

Best Regards,
tH3f0rC3

lentschi May 5, 2011 11:03

you can use paraView to show the epsilon values of your geometry!

tH3f0rC3 May 9, 2011 02:59

Quote:

Originally Posted by lentschi (Post 306382)
you can use paraView to show the epsilon values of your geometry!

So you think these values of epsilon are not realistic?
And do you know what is meant with continuity?
cumultative is plotted global and cumultative. As I understand, cumultative is the summed version of global.
But what is meant with global continuity?

Best Regards,
tH3f0rC3

lentschi May 9, 2011 03:33

Bounding variables sometimes occur. Their values depend amongst others on the geometry. So in your cae these values could be correct!

In my (complex) geometry, bounding variables occur too in some loadcases but I "have to live with them" and neglect them.

tH3f0rC3 May 9, 2011 03:43

Ah ok,
thanks for your answer!

Knigge46 February 20, 2015 05:40

Continuity
 
Am I right if I assume the "Continuity" plot to show the error of the solution of the continuity equation?

normally it should be zero that is (as far as I can see): no mass is added and nothing is lost.

Is this correct?

----

Another question:

why does the residual plot always show the first/initial residual of a timestep? shouldn't it be displaying the last/final residual after the iterations done?

zfaraday March 5, 2015 08:25

Hi all,
Quote:

Originally Posted by Knigge46 (Post 532630)
Another question:

why does the residual plot always show the first/initial residual of a timestep? shouldn't it be displaying the last/final residual after the iterations done?

It wouldn't make much sense because the residual of the last iteration is allways below the tolerance you defined in fvSolution unless the number of iterations is over the maximum number of iterations defined in the same file, in such case the solver stops with an error.

Regards,

Alex


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