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Polymer transport in random flow

A. Celani·S. Musacchio·D. Vincenzi
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Abstract

The dynamics of polymers in a random smooth flow is investigated in the framework of the Hookean dumbbell model. The analytical expression of the time-dependent probability density function of polymer elongation is derived explicitly for a Gaussian, rapidly changing flow. When polymers are in the coiled state the pdf reaches a stationary state characterized by power-law tails both for small and large arguments compared to the equilibrium length. The characteristic relaxation time is computed as a function of the Weissenberg number. In the stretched state the pdf is unstationary and exhibits multiscaling. Numerical simulations for the two-dimensional Navier-Stokes flow confirm the relevance of theoretical results obtained for the delta-correlated model.

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A. Celani, S. Musacchio, D. Vincenzi. 2004-10-19. Polymer transport in random flow. https://doi.org/10.1007/s10955-004-8820-6

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