Transport of inertial particles by viscous streaming in arrays of   oscillating probes
  A novel mechanism for the transport of microscale particles in viscous fluids is demonstrated. The mechanism exploits the trapping of such particles by rotational streaming cells established in the vicinity of an oscillating cylinder, recently analyzed in previous work. The present work explores a strategy of transporting particles between the trapping points established by multiple cylinders undergoing oscillations in sequential intervals. It is demonstrated that, by controlling the sequence of oscillation intervals, an inertial particle is effectively and predictably transported between the stable trapping points. Arrays of cylinders in various arrangements are investigated, revealing a quite general technique for constructing arbitrary particle trajectories. The timescales for transport are also discussed. 
Kwitae Chong, Scott D. Kelly, Stuart T. Smith and Jeff D. Eldredge
physics.flu-dyn