Drag reduction by polymers in turbulent channel flows: Energy redistribution between invariant empirical modes.

  title={Drag reduction by polymers in turbulent channel flows: Energy redistribution between invariant empirical modes.},
  author={Elisabetta De Angelis and Carlo Massimo Casciola and Victor S L’vov and Renzo Piva and Itamar Procaccia},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  volume={67 5 Pt 2},
We address the phenomenon of drag reduction by a dilute polymeric additive to turbulent flows, using direct numerical simulations (DNS) of the FENE-P model of viscoelastic flows. It had been amply demonstrated that these model equations reproduce the phenomenon, but the results of DNS were not analyzed so far with the goal of interpreting the phenomenon. In order to construct a useful framework for the understanding of drag reduction we initiate in this paper an investigation of the most… 

Time‐series and extended Karhunen–Loève analysis of turbulent drag reduction in polymer solutions

Direct numerical simulations and statistical analysis techniques are used to study the drag-reducing effect of polymer additives on turbulent channel flow in minimal domains. Additionally, a new

Viscoelastic effects on higher order statistics and on coherent structures in turbulent channel flow

In this work we study, using the results of direct numerical simulations [Housiadas and Beris, “Polymer-induced drag reduction: Viscoelastic and inertia effects of the variations in viscoelasticity

Modeling of viscoelastic turbulent flow in channel and pipe

This paper investigates turbulent flows with or without polymer additives in open channels and pipes. Equations of mean velocity, root mean square of velocity fluctuations, and energy spectrum are

Turbulent drag reduction and multistage transitions in viscoelastic minimal flow units

The observation that addition of a minute amount of flexible polymers to fluid reduces turbulent friction drag is well known. However, many aspects of this drag reduction phenomenon are not well

Effects of polymer stresses on eddy structures in drag-reduced turbulent channel flow

The effects of polymer stresses on near-wall turbulent structures are examined by using direct numerical simulation of fully developed turbulent channel flows with and without polymer stress. The

Inertia- and elasticity-driven turbulence in viscoelastic fluids with high levels of drag reduction

  • Lu Zhu
  • Engineering, Physics
  • 2019
In dilute polymer solution, polymers are able to change the flow structures and suppress the intensity of turbulence, resulting in a considerable friction drag reduction (DR). Despite the

Drag reduction and the dynamics of turbulence in simple and complex fluidsa)

Addition of a small amount of very large polymer molecules or micelle-forming surfactants to a liquid can dramatically reduce the energy dissipation it exhibits in the turbulent flow regime. This

Skin-Friction Drag Reduction by Dilute Polymer Solutions in Turbulent Channel Flow.

Skin-friction drag reduction by dilute polymer solutions is investigated using results from direct numerical simulations (DNS) of homogeneous polymer solutions in turbulent channel flow. Simulations



Stabilization of hydrodynamic flows by small viscosity variations.

This paper shows that the strong stabilization of the primary instability is also obtained when the viscosity profile is realistic (inferred from simulations of turbulent flows with a small concentration of polymers), and proposes that similar physics act in turbulent drag reduction.

Simple model for drag reduction.

  • R. BenziI. Procaccia
  • Physics
    Physical review. E, Statistical, nonlinear, and soft matter physics
  • 2003
A simple one-dimensional model of the FENE-P equations is introduced, drag reduction is demonstrated, and analytically the main observations are explained which include reduction of velocity gradients for fixed throughput and increase of throughput for fixed dissipation.

Scaling exponents in anisotropic hydrodynamic turbulence.

The main result of the calculation is that the scaling exponents zeta(2)(l) form a strictly increasing spectrum at least until l=6, guaranteeing that the effects of anisotropy decay as power laws when the scale of observation diminishes.

Thermodynamics of flowing systems : with internal microstructure

PART 1: THEORY Introduction 1. Symplectic geometry in optics 2. Hamiltonian mechanics of discrete particle systems 3. Equilibrium thermodynamics 4. Poisson brackets in continuous media 5.

Dynamics of Polymeric Fluids

  • 1987


  • 21, 625
  • 1975