[Goli]

Hello everyone,


I am simulating an incompressible flow around an airfoil in a rectangular domain by simpleFoam. I want to have periodic boundary condition on the top and bottom of the rectangle. The points on these two boundaries are the same and I used translational cyclic condition.



After running the simulation, the diagrams of the velocity of the periodic boundaries (top and bottom) do not match together in paraview.



I would be grateful if some one could help me.

[random_ran]

Please provide more details.


> I am simulating an incompressible flow around an airfoil in a rectangular domain by simpleFoam.

Good, we know what you are doing simulation using simpleFoam. However, we know little about the computational domain. What's it look like? How you define the coordinates, etc.

> I want to have periodic boundary condition on the top and bottom of the rectangle.

Why? on the top and bottom? It depends on how you define your geometry, i.e., the location of the air-wing.

>The points on these two boundaries are the same and I used translational cyclic condition.

How you define "the same"? If someone calculate a number but has a relative difference in 0.00000000000000001%. It is not the same, but we could think it is the same_.

>After running the simulation, the diagrams of the velocity of the periodic boundaries (top and bottom) do not match together in paraview.

Please show you picture.

Thank you,



> I would be grateful if some one could help me.

If sufficient information is ready.

[Goli]

Hello Ran,

Thank you for your reply. Attached (fig1) is a representation of the airfoils and the rectangles I want to simulate. Actually, I want to simulate one of these rectangles (the middle one) and put periodic BC on the top and the bottom of the rectangle.

Fortunately, the previous problem is solved by putting cyclicAMI instead of cyclic.

The only problem is that after running the simulation, it seems that there is no connection between the left side of the rectangle and the cyclic boundaries (top and bottom sides of the rectangle). I attached the pressure profile near the left side of the rectangle (fig2).

I imposed fixed value for the velocity and the pressure on the left side of the rectangle as the inlet.

Can I use cyclicACMI instead?

Thanks,
Goli