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arXiv · 2503.05897

Revealing Actual Viscoelastic Relaxation Times in Capillary Breakup

Nan Hu·Jonghyun Hwang·Tachin Ruangkriengsin·Howard A. Stone
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Abstract

We use experiments and theory to elucidate the size effect in capillary breakup rheometry, where pre-stretching in the visco-capillary stage causes the apparent relaxation time to be consistently smaller than the actual value. We propose a method accounting for both the experimental size and the finite extensibility of polymers to extract the actual relaxation time. A phase diagram characterizes the expected measurement variability and delineates scaling law conditions. The results refine capillary breakup rheometry for viscoelastic fluids and advance the understanding of breakup dynamics across scales.

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Nan Hu, Jonghyun Hwang, Tachin Ruangkriengsin, Howard A. Stone. 2025-03-07. Revealing Actual Viscoelastic Relaxation Times in Capillary Breakup. https://arxiv.org/abs/2503.05897

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