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jing August 26, 2003 10:24

Single rotating reference frame
 
Hi!

I am a bit of confused of configuration within a single rotating reference frame.

My flowfield, my boundary conditions are all rotating with a same velocity . In the inlet boundary, if I define U, V, W as relative veloctiy, should OMEGA at the inlet boundary panel be ZERO, or some other value? And, how about the OMEGA in the initialisation panel, if the UVW is also relative, should it be ZERO?

The monitored data is relative velocity, or absolute one, in which coordinate?

Thanks!

Jing

m-hack August 29, 2003 12:44

Re: Single rotating reference frame
 
Dear Jing,
with the rotation refecence frame you do not change any velocities, but you add centrifugal and coriolis forces to your momentum equations. If your complete region is rotating, you should define the OMEGA of your spinning fluid (Spin index of CTYPE). All velocities are then defined in your rotating frame, are therefore relative ones. As long as I know the OMEGA field in the BC window is used to define a swirl at the inlet. The vectors displayed should look somehow different, when applying swirl. Note that the units of OMEGA is the only one which is not SI! It's rpm.
Greetings, Marc


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