New publication in Physical Review Letters
June 2021 – As postulated by the Scallop Theorem, swimming at low Reynolds numbers requires non-reciprocity in time in the swimmer stroke. In our article entitled “Scallop Theorem and swimming at the Mesoscale” we employ a system of two connected asymmetric particles both having significant inertia and demonstrate a directed controlled swimmer motion even driven in a reciprocal fashion. The asymmetry in coasting times of the particles acts as a second degree of freedom and satisfies the scallop theorem. Our numerical lattice-Boltzmann simulations confirm the outcome of the analytical model whose predictions are approved in subsequent experiments using magnetic particles placed at an air/water interface.
This research is the result of a longstanding collaboration between the theoretical department of the Helmholtz Institute Erlangen-Nuernberg, the theory group of Prof. A. Smith (Friedrich-Alexander University) and the experimental department of Prof. N. Vandewalle (University of Liege, Belgium).