[rehaavsar]

Hi everyone!
I am trying to simulate an airfoil with increasing AOA from 0 till 20 degrees then it decreases to zero AOA.
Can anyone please help me how to do that in ANSYS Fluent or CFX?
Thanks.

More specifically I do not know how to create rotating airfoil. In geometry? In setup?

[davidwilcox]

If I understood you correctly, you are doing a problem related to dynamic stall (pitching). There are two ways you can do this. first is with a deforming mesh. The issue with the deforming mesh is that it is hard to refine the areas which are the most important especially on the suction side where you would expect a vortices to be convected or peeled, etc. This is because of the negative volume issue wrt to deforming meshes. You can definitely give this a go ( the concept is pretty similar to a way a spring deforms).
Another method is to rotate the whole computational domain in say the z axis ( x= chordwise, y =spanwise). You would need to set this up in the fluid zone where you have to supply an angular velocity and the axis of rotation ( take note of clockwise and anticlockwise direction i.e. plus or minus 1)

As for the meshing, you can pretty much "youtube" the procedure. There is nothing special you need to do. Everything is set up in Fluent.

[lfla]

Hello David,

I have been modelling that exact case and have succeeded with the deforming mesh only with a very coarse mesh as it is difficult to handle local remeshing.
I was wondering about the second option you suggested, would you have the fluid domain as a rigid body rotating as per the udf and the airfoil set as stationary? Thank you

[FMDenaro]

I would consider also the chance to use only a time-dependent inflow that changes the AOA without any change in the grid. That could be done in Fluent by using an UDF.