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arXiv · 2503.13168

Universal mean velocity profile in polymeric flows at maximum drag reduction

Francesco Serafini·Francesco Battista·Paolo Gualtieri·Carlo Massimo Casciola
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Abstract

Provided a sufficient concentration of long-chain polymers in a Newtonian solvent, turbulent wall-bounded flows exhibit a universal state known as Maximum Drag Reduction (MDR). Through direct numerical simulations, we show that the wall-normal kinetic energy flux characterising Newtonian wall-bounded turbulence is suppressed at MDR, and that the polymers mainly sustain velocity fluctuations. In agreement with the experimental data, we derive a universal expression for the mean velocity profile no longer dependent on characteristic quantities of wall-bounded turbulence.

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Francesco Serafini, Francesco Battista, Paolo Gualtieri, Carlo Massimo Casciola. 2025-03-17. Universal mean velocity profile in polymeric flows at maximum drag reduction. https://arxiv.org/abs/2503.13168

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