# Self-sustained elastoinertial Tollmien–Schlichting waves

@article{Shekar2020SelfsustainedET, title={Self-sustained elastoinertial Tollmien–Schlichting waves}, author={Ashwin Shekar and Ryan Michael McMullen and Beverley J. McKeon and Michael D. Graham}, journal={Journal of Fluid Mechanics}, year={2020}, volume={897} }

Direct simulations of two-dimensional plane channel flow of a viscoelastic fluid at Reynolds number $Re=3000$ reveal the existence of a family of attractors whose structure closely resembles the linear Tollmien–Schlichting (TS) mode, and in particular exhibits strongly localized stress fluctuations at the critical layer position of the TS mode. At the parameter values chosen, this solution branch is not connected to the nonlinear TS solution branch found for Newtonian flow, and thus represents…

## 17 Citations

The center-mode instability of viscoelastic plane Poiseuille flow

- Physics
- 2020

A modal stability analysis shows that plane Poiseuille flow of an Oldroyd-B fluid becomes unstable to a `center mode' with phase speed close to the maximum base-flow velocity, $U_{max}$. The…

Repicturing viscoelastic drag-reducing turbulence by introducing dynamics of elasto-inertial turbulence

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Abstract Recently, the nature of viscoelastic drag-reducing turbulence (DRT), especially the maximum drag reduction (MDR) state, has become a focus of controversy. It has long been regarded as…

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- Physics
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Using branch continuation in the FENE-P model, we show that finite-amplitude travelling waves borne out of the recently-discovered linear instability of viscoelastic channel flow (Khalid et al. J.…

Weakly nonlinear analysis of the viscoelastic instability in channel flow for finite and vanishing Reynolds numbers

- PhysicsJournal of Fluid Mechanics
- 2022

Abstract The recently discovered centre-mode instability of rectilinear viscoelastic shear flow (Garg et al., Phys. Rev. Lett., vol. 121, 2018, 024502) has offered an explanation for the origin of…

A reverse transition route from inertial to elasticity-dominated turbulence in viscoelastic Taylor–Couette flow

- Engineering, PhysicsJournal of Fluid Mechanics
- 2021

Abstract A high-order transition route from inertial to elasticity-dominated turbulence (EDT) in Taylor–Couette flows of polymeric solutions has been discovered via direct numerical simulations. This…

Continuous Pathway between the Elasto-Inertial and Elastic Turbulent States in Viscoelastic Channel Flow.

- Engineering, PhysicsPhysical review letters
- 2021

For highly elastic ultradilute polymer solutions, a single linearly unstable modal branch may underlie transition to elastic turbulence at zero Re and to elasto-inertial turbulence at moderate Re, implying the existence of continuous pathways connecting the turbulent states to each other and to the laminar base state.

Direct numerical simulation of inertio-elastic turbulent Taylor–Couette flow

- Physics, EngineeringJournal of Fluid Mechanics
- 2021

Abstract The flow physics of inertio-elastic turbulent Taylor–Couette flow for a radius ratio of $0.5$ in the Reynolds number ($Re$) range of $500$ to $8000$ is investigated via direct numerical…

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