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Adam Stuchlik March 11, 2009 07:20

Alternate Rotation Model
Ive problems to understand the functionality of this button. Could someone explain it simply?? best wishes adam

CycLone March 11, 2009 10:30

Re: Alternate Rotation Model
Hi Adam,

Enabling the alternate rotation model causes the solver to solve the advection term in the stationary frame and transform it back to the rotating frame. Enabling this option can reduce the production of false swirl, which occurs when your mesh is very coarse and/or your fluid motion is not well aligned with the rotating frame (i.e. flow through a fan, which is primarily axial is not well aligned with the rotating frame, whereas flow through a compressor, which follows the path between the vanes is very aligned).

This option is enabled if you use the turbo set-up mode in Pre, otherwise you need to turn it on yourself. There is no additional cost and while the improvement is more noticable on fans or vaneless spaces, it doesn't harm other cases, so there is no harm in always enabling it. It is not enabled by default for backwards compatibility with cases set up in earlier versions of the code that did not have this option.


Jasmine March 27, 2009 14:36

Is the Alternate rotation model availabe for General Cases? Where is the setting button actually?

em... i found it just now. It can be chosen when you set the domain rotating speed.

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