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arXiv · 2508.08862

Saddle-node bifurcation during the relaminarization of turbulent puffs in pipe

Basheer Ahmad Khan·Shai Arogeti·Oriel Shoshani·Alexander Yakhot
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Abstract

Turbulent puffs in a pipe persist for a long time before abruptly transitioning to laminar flow through viscous exponential decay. Direct numerical simulation results reveal a saddle-node bifurcation sequence governing the final relaminarization stage. Specifically, a universal square-root scaling law in the annihilation of critical points that is indicative of a saddle-node bifurcation. The Riccati equation has been proposed as a straightforward approach to modeling these bifurcations.

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Basheer Ahmad Khan, Shai Arogeti, Oriel Shoshani, Alexander Yakhot. 2025-08-12. Saddle-node bifurcation during the relaminarization of turbulent puffs in pipe. https://arxiv.org/abs/2508.08862

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