I wonder how to apply extrapolation scheme in outlet flow condition in 2D cases. I know that in 3D the function setWallFunctionBoundary can do that,but how about in 2D cases?
setWallFunctionBoundaryuses its own implementation for extrapolation in 3D, which is not shared with other BCs for now. If you’re looking for something non-local for the outlet I would suggest setInterpolatedPressureBoundary.
But if you’re specifically after extrapolation, I’m afraid you’d have to implement it yourself.