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udf for changing rotational velocity

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Old   September 24, 2010, 03:16
Default udf for changing rotational velocity
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Hi,

I'd like to create an UDF to change the wall rotation during an unsteady simulation after a certain amount of time.

It seems that I can't put the UDF in the wall settings if I'm selecting a rotating wall.

Is there an easy solution or do I have to select "components" instead of "rotational" and change the UDF?

Thanks for your help,

peter
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Old   September 24, 2010, 04:03
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There is a macro called THREAD_VAR(thread).wall.omega
that can be used to set the rotational speed (rad/s) for a given wall-thread. Your udf can't be hooked in the BC-menue of this wall but you may use e.g. DEFINE_ADJUST or EXECUTE_AT_END to update the rotation speed. In the GUI you will still see a constant (initial) value but it will change actually according to your specifications.

cheers
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Old   September 24, 2010, 04:24
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Sounds good, thanks for the advice
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Old   September 29, 2010, 11:43
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Another alternative is to use a scheme script that is run every time step. In this script you may use a TUI command to setup your rotating wall velocity.
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Old   October 19, 2010, 06:43
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Quote:
Originally Posted by coglione View Post
There is a macro called THREAD_VAR(thread).wall.omega
that can be used to set the rotational speed (rad/s) for a given wall-thread. Your udf can't be hooked in the BC-menue of this wall but you may use e.g. DEFINE_ADJUST or EXECUTE_AT_END to update the rotation speed. In the GUI you will still see a constant (initial) value but it will change actually according to your specifications.

cheers
I tried using the macro, but I always get the ACCESS_VIOLATION error.
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