Transition in pipe flow: the saddle structure on the boundary of turbulence
TLDR
The laminar-turbulent boundary Sigma is the set separating initial conditions which relaminarize uneventfully from those which become turbulent as discussed by the authors, and is defined as the boundary that separates initial conditions from those that become turbulent.Abstract:
The laminar-turbulent boundary Sigma is the set separating initial conditions which relaminarize uneventfully from those which become turbulent. Phase space trajectories on this hypersurface in cyl ...read more
Citations
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Dynamics and Control of Global Instabilities in Open-Flows: A Linearized Approach
TL;DR: In this article, the dynamics and control of low-frequency unsteadiness, as observed in some aerodynamic applications, were addressed, and a coherent and rigorous linearized approach was presented, which enables both to describe the dynamics of commonly encountered open-flows and to design open-loop and closed-loop control strategies, in view of suppressing or delaying instabilities.
Journal ArticleDOI
Triggering in the horizontal Rijke tube: non-normality, transient growth and bypass transition
TL;DR: In this article, a procedure is developed to find the lowest initial energy that can trigger self-sustained oscillations, as well as the corresponding initial state, known as the "most dangerous" initial state.
Journal ArticleDOI
Numerical Bifurcation Methods and their Application to Fluid Dynamics: Analysis beyond Simulation
Henk A. Dijkstra,Fred Wubs,Andrew K. Cliffe,Eusebius J. Doedel,Ioana F. Dragomirescu,Bruno Eckhardt,Alexander Yu. Gelfgat,Andrew L. Hazel,Valerio Lucarini,Andrew G. Salinger,Erik T. Phipps,Juan Sanchez-Umbria,Henk M. Schuttelaars,Laurette S. Tuckerman,Uwe Thiele +14 more
TL;DR: Numerical bifurcation analysis of high-dimensional dynamical systems has been extensively studied in the literature as discussed by the authors, where the authors provide an overview of current techniques and typical applications of such problems in fluid dynamical problems.
Journal ArticleDOI
Theoretical perspective on the route to turbulence in a pipe
TL;DR: The route to turbulence in pipe flow is a complex, nonlinear, spatiotemporal process for which an increasingly clear theoretical understanding has emerged as discussed by the authors, exploiting analogies to coexisting thermodynamic phases and to excitable and bistable media.
Journal ArticleDOI
On coherent structure in wall turbulence
Ati S. Sharma,Beverley McKeon +1 more
TL;DR: McKeon et al. as discussed by the authors proposed a new theory of coherent structure in wall turbulence, based on an analysis of the Navier-Stokes equations, under an assumption of a turbulent mean profile.
References
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An Experimental Investigation of the Circumstances Which Determine Whether the Motion of Water Shall Be Direct or Sinuous, and of the Law of Resistance in Parallel Channels
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The minimal flow unit in near-wall turbulence
Javier Jiménez,Parviz Moin +1 more
TL;DR: In this article, the authors performed direct numerical simulations of unsteady channel flow at low to moderate Reynolds numbers on computational boxes chosen small enough so that the flow consists of a doubly periodic array of identical structures.