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arXiv · 1802.04871

Tumbling dynamics of inertial chains in extensional flow

Christophe Henry·Giorgio Krstulovic·Jérémie Bec
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Abstract

The dynamics of elongated inertial particles in an extensional flow is studied numerically by performing simulations of freely jointed bead-rod chains. The coil-stretch transition and the tumbling instability are characterized as a function of three parameters: The Peclet number, the Stokes number and the chain length. Numerical results show that in the limit of infinite chain length, particles are trapped in a coiled or stretched state. The coil-stretch transition is also shown to depend non-linearly on the Stokes and Peclet number. Results also reveal that tumbling occurs close to the coil-stretch transition and that the persistence time is a non-linear function of Stokes and Peclet numbers.

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Christophe Henry, Giorgio Krstulovic, Jérémie Bec. 2018-02-13. Tumbling dynamics of inertial chains in extensional flow. https://doi.org/10.1103/physreve.98.023107

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