swirling jet
 

Dear formers,
I succeeded in doing liquid jet from a circular orifice in side a cuboid by starting this jet from above it( in the z direction) ,and now I am trying to give this jet a swirl. My question is: There are any boundary conditions for imposing swirl or I have to do it by doing a geometry? . I am using OF 2.1.1 and interFoam as a solver. Please and thoughts would help.
Sandy,:)