Cyclones and attractive streaming generated by acoustical vortices
  Acoustical and optical vortices have attracted large interest due to their ability in capturing and manipulating particles with the use of the radiation pressure. Here we show that acoustical vortices can also induce axial vortical flow reminiscent of cyclones whose topology can be controlled by adjusting the properties of the acoustical beam. In confined geometry, the phase singularity enables generating attractive streaming with a flow directed toward the transducer. This opens perspectives for contact-less vortical flow control. 
Antoine Riaud and Michael Baudoin and Jean-Louis Thomas and Olivier   Bou Matar
physics.flu-dyn physics.class-ph