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

2025/08/12 by Basheer A. Khan, Shai Arogeti, Khan, Basheer Ahmad +5
Engineering · #Fluid Dynamics and Turbulent Flows #Aerodynamics and Acoustics in Jet Flows #Particle Dynamics in Fluid Flows

paper · pdf · doi:10.48550/arxiv.2508.08862

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.

Citations

• Relaminarization of turbulent puffs in pipe flow
• Critical Behaviour in the Relaminarisation of Localised Turbulence in Pipe Flow

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