Inspired by the Flapping Wings of a Bird: Invention of a New Ratchet Pump

NYU Shanghai professor of physics and mathematics Jun Zhang and Benjamin Thiria, researcher at ESPCI ParisTech, just published in a research journal Applied Physics Letters, from AIP Publishing on February 3, 2015.
“Ratcheting Fluid with Geometric Anisotropy” details the seemingly surprising results of their experimental findings.
Imagine the flight of a bird—with each wing flap, air is pushed in one direction while the bird itself travels in the other. In a way, the air is pumped backwards by the flapping wings. The researchers were inspired by this natural mastery of fluid dynamics to create a ratchet pumping mechanism that moves fluid using vibration or shaking instead of a rotor; while the latter has been a crucial piece in all of the pumps we use today.
"When a fluid is squeezed and expanded repeatedly between two saw-toothed plates, the asymmetric boundary forces the fluid to move in one direction," says Zhang. The result is an unidirectional transportation of fluid that provide an alternative means to mobilize fluids.
The reported study demonstrates the physical principles of fluid pumping without any rotational element in a system. Practical application of the ratchet pump will find their ways in industrial settings, where excessive vibrations of heavy machinery are unwanted and wasted. The newly invented pump could harvest such vibrational energy (and thus the loud noise) and convert it to useful work while improving the longevity of machines, leading to a more productive and safer working environment.

Professor Jun Zhang is also a standing member of NYU-ECNU Institute of Mathematical Sciences at NYU Shanghai.