Experimental investigations of metachronal synchronization in 2D cilia arrays

• Applicants: Professor Dr.-Ing. Christoph Brücker; Professor Dr.-Ing. Uwe Schnakenberg
• Subject Area: Fluid Mechanics ; Theoretical Condensed Matter Physics
• Term: from 2014 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 254471792

• Final Report Year: 2016

Final Report Abstract

A biomimetic pneumatically actuated artificial 1D cilia array made of poly(dimethylsiloxane) (PDMS) mimicking a comb row of ctenophore Pleurobrachia pileus was improved to investigate the transport behavior of fluid near the ciliated wall. The transport depends significantly on the inclination angle of the flap. Structures with flaps of inclination angles of between 0° and 45° were characterized. The results of experiments agree well with those of the FEM- based simulations. Antiplectic fluid transport was observed for flap inclination angles lower than 20° whereas symplectic fluid transport was observed for inclination angles higher than 20°. Symplectic fluid transport can be achieved over a wider range of inclination angles. The good agreement between simulation and experimental results indicates that the developed simulation tool should be used for improving the design and prediction of fluid transport for future applications. More detailed investigations on arrays with 45° tilted flaps show that fluid velocity increases with beating frequency. A maximum velocity of 319 µm/s was observed for symplectic fluid transport at beating frequencies of 5 Hz. The direction of the travelling wave - either symplectic or antiplectic - does not affect the direction of overall flow transport. 2D arrays with 5 * 5 membranes were successfully developed to enable individually addressable membranes. The membranes were connected to high speed valves switchable within only 2 ms. To actuate the valves a custom-made analog amplifier in combination with reloadable capacitors was developed.

Publications

• Fluid transport via pneumatically actuated waves on a ciliated wall, J. Micromech. Microeng. 25 125009 (8 pp) (2015)
  A. Rockenbach, V. Mikulich, Ch. Brücker, U. Schnakenberg
  
• The Influence of flap inclination angle on fluid transport at ciliated walls. J. Micromech. Microeng. 27 015007 (8pp) (2017)
  A. Rockenbach, U. Schnakenberg