(230am) Two Spheres and a Spring Make a Good Swimmer
AIChE Annual Meeting
2016
2016 AIChE Annual Meeting
Engineering Sciences and Fundamentals
Poster Session: Fluid Mechanics (Area 1J)
Monday, November 14, 2016 - 3:15pm to 5:45pm
Rigid spherical particles in oscillating fluid flows form interesting patterns as a result of fluid mediated interactions, at intermediate Reynolds numbers. Here, through both experiments and simulations, we show that two spheres under horizontal vibration align themselves at right angles to the oscillation and sit with a gap between them, which scales in a non-classical way with the boundary layer thickness. A large number of spherical particles form strings perpendicular to the direction of oscillation. Investigating the details of the interactions we find that the driving force is the nonlinear hydrodynamic effect of steady streaming. We then design a simple swimmer (two-spheres-and-a-spring) that utilizes steady streaming in order to propel itself and discuss the nature of the transition at the onset of swimming as the Reynolds number gradually increases. We discuss our latest results on the collective behavior of simple swimmers at intermediate Reynolds numbers.