Jittery velocity relaxation of an elastic sphere immersed in a viscous incompressible fluid

B. U. Felderhof

doi:10.1103/physreve.89.033001

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arXiv · 1312.3842

Jittery velocity relaxation of an elastic sphere immersed in a viscous incompressible fluid

B. U. Felderhof

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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.

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B. U. Felderhof. 2014-02-21. Jittery velocity relaxation of an elastic sphere immersed in a viscous incompressible fluid. https://doi.org/10.1103/physreve.89.033001

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