Meeting Abstract
15.1 Sunday, Jan. 4 Ciliary Transport and Flagellar Locomotion in Physical Models with Varying Reynolds Numbers TAPPE, J.T.*; SANTHANAKRISHNAN, A.; MILLER, L.A.; University of North Carolina at Chapel Hill tappe@email.unc.edu
Swimming organisms have adapted varying methods of locomotion such as cilia, flagella, fins, and jet propulsion. Fluid environments with low Reynolds numbers are inhabited by many organisms such as bacteria. E.M. Purcell (American Journal of Physics, 1976) published research which showed that at very low Reynolds numbers reciprocal motion in which pumping or swimming is achieved by a reversible process is not an effective means of moving or moving through fluid. For the case of locomotion, results from an experimental investigation of flagellar locomotion using physical vessels modelled after biological organisms are examined over Reynolds numbers ranging from 10-3 to 10. For the case of fluid transport in the same range of Reynolds numbers, a physical model of a single cilium is examined. Quantitative and qualitative flow visualizations are used to understand the limit at which both flagellar locomotion in terms of forward velocity and ciliary transport in terms of volumetric transport are no longer efficient. Furthermore, the data obtained allows characterization of the efficiency as a function of Reynolds number and indicates whether the relationship is gradual, drastic, or intermediate. This provides insight as to the effects of scaling in organisms and why only the very small exhibit the features being investigated in this experiment.
