Gears Without Teeth: Fluid Flows Spin Rotors in a Noncontact Engine
NYU researchers demonstrate fluid-driven gear-like coupling: two submerged rotors in a glycerol–water mix generate motion in a passive rotor via controlled liquid flows. By adjusting distance and rotation speed, the system can mimic interlocking gears (opposite directions) or belt-and-pulley systems (same direction), offering a tunable, noncontact alternative to traditional gears. Published in Physical Review Letters with NSF support.