title: Jittery velocity relaxation of an elastic sphere immersed in a viscous incompressible fluid.
abstract: Velocity relaxation of an elastic sphere immersed in a viscous incompressible fluid is studied on the basis of the equations of linear elasticity and the linearized Navier-Stokes equations. It is found that both translational motion after a sudden impulse and rotational motion after a sudden twist show jittery behavior in the long-time regime, with many reversals of velocity if the sphere is sufficiently flexible. In the extreme long-time regime the translational and rotational velocity relaxation functions each decay with a universal algebraic long-time tail. The added mass and the added moment of inertia of the sphere are found to vanish.
authors.affiliation: Institute for Theoretical Physics A, RWTH Aachen University, Templergraben 55, 52056 Aachen, Germany.
authors.forename: B U
authors.initials: BU
authors.lastname: Felderhof