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Imbalance in %, Y-axis scale correct?

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Old   March 31, 2011, 12:48
Default Imbalance in %, Y-axis scale correct?
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Dan
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I am running a 3D simulation in CFX using k-omega SST.

I am monitoring the run and I plotted Energy, Mass and Momentum imbalance on the same monitor chart that residuals are plotted, this chart is logarithmic Y-axis.

My question is, it says the H, U and P balances are being shown in %, if this true please confirm, because the simulation is at 1e-1 which is 0.1%, and this can easily be mistaken for 10% if it is not clear that the scale is showing actual percent values and not decimal values (for the three balance variables).

Thank you
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Old   March 31, 2011, 13:56
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I agree it's not clear, but it is a percentage. Stop the run and compare to the values printed in the .out file.
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Old   April 1, 2011, 03:34
Default Don't stop the run
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Please dont stop the run, you can just change the parameters to be plotted in the present monitor by right clicking on the plot area of the screen. Yopu can create a seperate monitor by cliking the right mouse button on the tabs above the monitros and declare a new monitor and plot any of the available parameters

-Dinesh
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Old   April 1, 2011, 03:35
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Also click on the respective curve and u can see the current value....btw imbalances are always shown in % but residuals are never ( % of what ? )
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Old   August 31, 2013, 15:39
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can you tell me how to monitor imbalance?i cant find it out?
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Old   September 1, 2013, 05:49
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You can view the imbalances in the solver manager -Edit the data displayed on the plot to imbalances.

The imbalance is simply a % imbalance of total amount of that variable in the domain. So it checks the global conservation of the variables.
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Old   September 1, 2013, 09:01
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you mean by defining a new monitor in Solver manager ?but i cant find the imbalance in the options!
there is only
Residual>max and RMS>..
and there is no imbalance .i cant find it.don't you mean that i should define an expression in cfx pre as imbalance and setup a monitor for that?or there is something in the solver manager?
pleas guide me through this.
thanks alot
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Old   September 1, 2013, 18:38
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Monitor properties - plot line variable - "Residual" is one key term, and "imbalance" is another. Look under imbalance.
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Old   September 2, 2013, 09:20
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i don't know why there is no imbalance in the plot variable page !
it there any option in the CFX pre that must be activated to monitor imbalance which i skipped or ignored ?
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Old   September 2, 2013, 13:00
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i have find it in the monitor option in CFX PRE. thanx Glenn
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