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arXiv · 2310.05340

A unified view of elastic and elasto-inertial turbulence in channel flows at low and moderate Reynolds numbers

Giulio Foggi Rota·Christian Amor·Soledad Le Clainche·Marco Edoardo Rosti
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Abstract

The chaotic flow of elastic fluids at low Reynolds number (Re) is typically distinguished into elasto-inertial and elastic turbulence (EIT/ET). However, the clear separation among these two turbulent regimes in parallel flows with a gradual Re decrease remains elusive. Here, spanning Re over four orders of magnitude, we investigate the statistical and structural nature of the flows computed by fully resolved 3D numerical simulations, revealing that as inertia becomes sub-dominant all flows share similar dynamical properties. Supported by the results, we thus propose a unified view of fully developed ET and EIT in parallel flows.

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Giulio Foggi Rota, Christian Amor, Soledad Le Clainche, Marco Edoardo Rosti. 2023-10-09. A unified view of elastic and elasto-inertial turbulence in channel flows at low and moderate Reynolds numbers. https://doi.org/10.1103/physrevfluids.9.l122602

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