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arXiv · 1012.1978

Deformation of a flexible polymer in a random flow with long correlation time

Stefano Musacchio·Dario Vincenzi
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Abstract

The effects induced by long temporal correlations of the velocity gradients on the dynamics of a flexible polymer are investigated by means of theoretical and numerical analysis of the Hookean and FENE dumbbell models in a random renewing flow. For Hookean dumbbells, we show that long temporal correlations strongly suppress the Weissenberg-number dependence of the power-law tail characterising the probability density function (PDF) of the elongation. For the FENE model, the PDF becomes bimodal, and the coil-stretch transition occurs through the simultaneous drop and rise of the two peaks associated with the coiled and stretched configurations, respectively.

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Stefano Musacchio, Dario Vincenzi. 2010-12-09. Deformation of a flexible polymer in a random flow with long correlation time. https://doi.org/10.1017/s0022112010006385

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