Propulsion at low Reynolds number

Abstract

We study the propulsion of two model swimmers at low Reynolds number. Inspired byPurcell’s model, we propose a very simple one-dimensional swimmer consisting of threespheres that are connected by two arms whose lengths can change between two values. Theproposed swimmer can swim with a special type of motion, which breaks thetime-reversal symmetry. We also show that an ellipsoidal membrane with tangentialtravelling wave on it can also propel itself in the direction preferred by the travellingwave. This system resembles the realistic biological animals like Paramecium.