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Old   September 4, 2013, 09:19
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Jerrica Lee
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I'm modeling a transient case, how can I get time-averaged velocity in CFX Post, that is to say to average the velocity of several timesteps. Thank you in advance
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Old   September 6, 2013, 10:10
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Erik
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You could output the transient results yourself using the chart option. Then average them yourself in excel or some other software.
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Old   September 6, 2013, 10:46
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If you're talking about the velocity field for the entire domain, there are ways to do that, but they need so much work that they're not even worth talking about.

What you should do is go back to your setup and, on Output Control, create a new 'Transient Average' object. In there you can set a time averaged variable for velocity (and/or for each velocity component). Unfortunately this involves re-running your simulation.

If it's only for some points/regions of your domain, you can do what Erik mentioned, but you'll be limited to the frequency used to export the transient files. Next time, use a monitor point to export the data from every timestep.
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Old   September 6, 2013, 19:12
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I agree with brunoc. As a conservative measure I always turn on transient average statistics of essential variables. Obviously if I want to monitor a specific transient average variable which isn't in the standard list then I include it in the additional variables list.
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Old   September 9, 2013, 06:32
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Jerrica Lee
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well, it seems that the huge work load involved would make me crazy! But thank you all the same
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Old   September 9, 2013, 06:35
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Jerrica Lee
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Thank you for your suggestion. But I'm wondering how to create a new 'Transient Average' object on Output Control, can you show me more details?
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Old   September 9, 2013, 06:42
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Lance
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Double click on Output control
Click on Trn Stats tab
Click on "Add new item" icon
Click on OK
Check that Option: Arithmetic Average
Check that Output Variables List: Velocity
Click on OK

Do you need more detailed instructions?
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Old   September 10, 2013, 04:36
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Oh I got it, thank you so much
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