LAUSR

In optimizing fluid flow at walls, research has turned to artificial cilia to mimic the propulsion of their whip-like beat of a metachronal traveling wave. Recently we developed a pneumatically actuated micro-membrane device which has rows of long flaps positioned off-center on membranes over a row of cavities, much like the comb row of a ctenophore. As little is known about how the flap inclination angle influences the fluid transport near the wall of such devices, this paper presents a detailed modeling and experimental investigation of this question using combined FEM-FVM (finite element method-finite volume method)-based simulations for inclination angles of 0°, 20°, 30°, and 45°. The experimental results agree well with those of the FEM-FVM simulations. Antiplectic fluid transport was observed for flap inclination angles lower than 20° whereas symplectic fluid transport was determined for those higher than 20°. In conclusion, the inclination angle of the flaps decisively affects the fluid transport direction and velocity.