[Roh]

Guys,


I'm thinking to simulate interior part(Intake) of jet engine with its spinner. The domain is something like this(the blue area is the domain):




My simulation is supposed to be axisymmetric 2D and spinner shoud be spinning but I don't know how to add a spinning speed to the spinner. Any suggestion for doing this project?

[LuckyTran]

The spinner can be a no-slip wall with a velocity applied.

[Roh]

Originally Posted by LuckyTran

The spinner can be a no-slip wall with a velocity applied.

Thank you for reply,
I was digging the manual of Fluent and now I think I know what to do but, there is a question to me. I don't know What kind of velocity formulation should I use. Relative velocity formulation or Absolute velocity formulation?


I'm going to do a 2D-axisymmetric for this work. Here is the domain:





https://www.cfd-online.com/Forums/at...1&d=1563200001



I was reading this slide (slide number = 20):


https://slideplayer.com/slide/9398929/


In my domain, I have two walls, the case and spinner. The case is stationary and the spinner is rotating around the axis. As is said here:


http://www.afs.enea.it/project/neptu...ug/node250.htm

...For 2D axisymmetric problems, you will not define the axis: the rotation will always be about the axis, with the origin at (0,0)....

Ok, and in that slide we see this coordinate system:





https://www.cfd-online.com/Forums/at...1&d=1563200001

I'm confused what kind of velocity formulation I need to use. I think that Relative velocity formulation is for the cases that the rotating element are not located on (0,0,0) coordinate and there is a distance between the interested element and (0,0,0) coordinate. Am I right? Then in my case, there is no difference what to choose. I guess we always can use relative velocity formulation. Indeed which one should I choose?

[LuckyTran]

It is a cartoon, but your domain looks right. For 2d axissymmetric problems, the axis of symmetry is fixed.


However, you can still define wonky coordinate systems and corresponding wonky velocities.


It never matters which formulation you use (absolute or relative) as long as you know what you are doing. So pick one that that makes sense to you, that you understand, and that works for you.