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arXiv · 2507.11923

Steady-state extensional viscosity of wormlike micellar solutions via dissipative particle dynamics simulations

Yusuke Koide·Takato Ishida·Takashi Uneyama·Yuichi Masubuchi
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Abstract

We investigate the steady-state extensional viscosity of wormlike micellar solutions using dissipative particle dynamics simulations. As the extension rate increases, the steady-state extensional viscosity initially increases and subsequently decreases after reaching a maximum, as observed in experiments. We reveal that this nonmonotonic behavior arises from the competition between micellar stretching and scission under uniaxial extensional flow. We further propose a relation that connects the extensional viscosity to micellar structures and kinetics. This relation provides a unified description of the extensional viscosity of unentangled wormlike micellar solutions for various temperatures, concentrations, and extension rates.

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Yusuke Koide, Takato Ishida, Takashi Uneyama, Yuichi Masubuchi. 2025-07-16. Steady-state extensional viscosity of wormlike micellar solutions via dissipative particle dynamics simulations. https://arxiv.org/abs/2507.11923

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