title: Lifetime of a cluster of spheres settling under gravity in Stokes flow.
abstract: The evolution of a cluster of three identical nontouching spheres settling in a vertical plane due to gravity in Stokes flow has been evaluated numerically for a two-parameter family of initial configurations, with the sphere centers close to each other and located on a horizontal line. A condition has been specified which relates the cluster lifetime to its geometry. The cluster lifetime and the label of the sphere left behind are very sensitive to initial conditions, as within the point-particle approximation of Jánosi et al. [Phys. Rev. E 56, 2858 (1997)]. The finding is that an increase of the sphere radii always reduces the range of initial conditions leading to chaotic scattering. The hydrodynamic interactions between close spheres stabilize the cluster.
authors.affiliation: Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, PL-02-106 Warsaw, Poland.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Ekiel-Jeżewska
authors.forename: Eligiusz
authors.initials: E
authors.lastname: Wajnryb