Dedicated U turn segments
Dedicated U turn segments in the New Orleans metropolitan area (at least) shall be named "U turn". Since U turn segments in Jefferson Parish (at least) are signed as such, and since Jefferson Parish comprises a large portion of the metropolitan area, it's best to keep the naming of U turn segments consistent.
The geometry of the segment should be set such that the instruction onto the U turn will be "turn left". For more heavily curved U turn segments, zoom in and insert a geometry node near the first junction node to create roughly a 90° angle with the road as shown in this section of the Junction Style Guide.