Accurate statistics of a flexible polymer chain in shear flow

Dibyendu Das; Sanjib Sabhapandit

doi:10.1103/physrevlett.101.188301

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arXiv · 0809.2131

Accurate statistics of a flexible polymer chain in shear flow

Dibyendu Das·Sanjib Sabhapandit

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Abstract

We present exact and analytically accurate results for the problem of a flexible polymer chain in shear flow. Under such a flow the polymer tumbles, and the probability distribution of the tumbling times $τ$ of the polymer decays exponentially as $\sim \exp(-ατ/τ_0)$ (where $τ_0$ is the longest relaxation time). We show that for a Rouse chain, this nontrivial constant $α$ can be calculated in the limit of large Weissenberg number (high shear rate) and is in excellent agreement with our simulation result of $α\simeq 0.324$. We also derive exactly the distribution functions for the length and the orientational angles of the end-to-end vector of the polymer.

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BibTeX RIS

Dibyendu Das, Sanjib Sabhapandit. 2008-11-13. Accurate statistics of a flexible polymer chain in shear flow. https://doi.org/10.1103/physrevlett.101.188301

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