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Inlet velocity as a function of time. Transient analysis.

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Old   December 11, 2012, 07:58
Default Inlet velocity as a function of time. Transient analysis.
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Christian Elgård Nielsen
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Hello,

Does anybody know if it is possible to setup an inlet boundary with userdefined velocity as a function of time.

What i would like to do is set the velocity to 0m/s for 0->1s and then 10m/s for 1->10s.

Is it possible to set up a table, or in any other way define the velocity in a more advanced way?

/Elgaard
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Old   December 11, 2012, 08:01
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Lance
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Your example can easily be solved using an expression with step functions. For more advanced profiles see http://www.edr.no/blogg/ansys_blogge...nsient_profile (or search this forum...)
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Old   December 11, 2012, 09:03
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Christian Elgård Nielsen
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Thank you. I am quite new to CFX, but this helped a lot. Found a manual for the CEL language, and got it to work.

Manual: http://hikwww2.fzk.de/hik/orga/hlr/A...xpres_lang.pdf

Expression: step(t*1[s^-1]-1)*10[m s^-1]

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Old   December 12, 2012, 02:36
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The manuals come with the installation, usually located at:
C:\Program Files\ANSYS Inc\v140\commonfiles\help\en-us\pdf
or by pressing F1 inside CFX.
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