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Relative velocity in simpleSRFFoam

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Old   November 4, 2008, 08:39
Default Hi, I have a question to simpl
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Miku
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Hi, I have a question to simpleSRFFoam. I cannot find a definition of Urel. Relative to what is Urel? And why does simpleSRFFoam use Urel instead of U absolute?
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Old   November 4, 2008, 09:21
Default Hi Miku, Urel is the relati
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Hi Miku,

Urel is the relative velocity in the rotational frame, the absolute velocity would then be:

Uabs = Urel + omega x R

where omega is the angular velocity vector and R the position vectro in rotational frame.
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Old   November 4, 2008, 09:35
Default Hi Miku, Maybe you will find
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Hi Miku,
Maybe you will find this answer satisfactory: relative velocity formulation


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Old   November 4, 2008, 10:26
Default Thanks for your answers! If I
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Thanks for your answers!
If I have not defined a rotational frame and my rotational axis is equivalent to the z-axis of my stationary coordinate system, I am right that my relative velocity is equivalent to my absolute velocity?

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Old   November 4, 2008, 10:51
Default Hi Miku, The relative velocit
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Hi Miku,
The relative velocity is identical to the absolute one, when there is no transport velocity (in your case 0 rotation or 0 rpm).

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