Swimming with a friend at low Reynolds number

摘要: We investigate the hydrodynamic interactions between microorganisms swimming at low Reynolds number. By considering simple model swimmers, and combining analytic numerical approaches, we time-averaged flow field around a swimmer. At short distances swimmer behaves like pump. large velocity depends on whether stroke is invariant under combined time-reversal parity transformation. then consider two swimmers find that interaction them consists of parts; dead term, independent motion second swimmer, which takes expected dipolar form live term resulting from simultaneous action both does not. argue that, in general, latter dominates. The swimmer--swimmer complicated function their relative displacement, orientation phase, leading to can be attractive, repulsive or oscillatory.