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arXiv · 2508.15349

The Role of Vortex Stretching in Drag Reduction of Polymer-Laden Turbulent Flow

Wouter J. T. Bos·Xuan Shao·Tong Wu·Le Fang
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Abstract

An addition of polymers can significantly reduce drag in wall-bounded turbulent flows, such as pipes or channels. This phenomenon is accompanied by a noticeable modification of the mean velocity profile. Starting from the premise that polymers reduce vortex-stretching, we derive a theoretical prediction for the mean-velocity profile. After assessing this prediction by numerical experiments of turbulence with reduced vortex stretching, we show that the theory successfully describes experimental measurements of drag-reduction in pipe-flow.

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Wouter J. T. Bos, Xuan Shao, Tong Wu, Le Fang. 2025-08-21. The Role of Vortex Stretching in Drag Reduction of Polymer-Laden Turbulent Flow. https://arxiv.org/abs/2508.15349

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