Hello Folks,
I am trying to use the Forward Navier stokes solver example from The FEniCSx tutorials by Jørgen S. Dokken for a project.
I wanted to use the same setup but simulate a far-flow condition by using open or slip conditions at the walls.
I tried looking at the forum but was unable to find anything that could help me. If somebody could point me in the right direction, it would be highly appreciated. I thank you for your time and patience.
Sincerely,
A new Fenics user 
Slip conditions can be done easily with dirichlet bcs on sub spaces if your boundary is aligned with the cartesian grid.
However, if it is not aligned, I would suggest you to have a look at:
https://jsdokken.com/dolfinx_mpc/python/demos/demo_stokes.html
which shows how to use multi-point constraints to do slip condtions.
A final approach would be to enforce slip weakly, through a Nitsche-type formulation.
Thank you Dokken! I will use these approaches and let you know if they have worked