title: A circle swimmer at low Reynolds number.
abstract: Swimming in circles occurs in a variety of situations at low Reynolds number. Here we propose a simple model for a swimmer that undergoes circular motion, generalising the model of a linear swimmer proposed by Najafi and Golestanian (Phys. Rev. E 69, 062901 (2004)). Our model consists of three solid spheres arranged in a triangular configuration, joined by two links of time-dependent length. For small strokes, we discuss the motion of the swimmer as a function of the separation angle between its links. We find that swimmers describe either clockwise or anticlockwise circular motion depending on the tilting angle in a non-trivial manner. The symmetry of the swimmer leads to a quadrupolar decay of the far flow field. We discuss the potential extensions and experimental realisation of our model.
authors.affiliation: The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, UK. r.ledesmaaguilar1@physics.ox.ac.uk
authors.forename: R
authors.initials: R
authors.lastname: Ledesma-Aguilar
authors.forename: H
authors.initials: H
authors.lastname: Löwen
authors.forename: J M
authors.initials: JM
authors.lastname: Yeomans