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Related papers: Turbulent shear layers in confining channels

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Scaling and structural evolutions are contemplated in a new perspective for turbulent channel flows. The total integrated turbulence kinetic energy remains constant when normalized by the friction velocity squared, while the total…

Fluid Dynamics · Physics 2021-05-19 T. -W. Lee

Lagrangian tracking of particle pairs is of fundamental interest in a large number of environmental applications dealing with contaminant dispersion and passive scalar mixing. The aim of the present study is to extend the observations…

Buoyancy effects in unstably stratified mixing layers express themselves through gravity currents of heavy fluid which propagate in an ambient lighter fluid. These currents are encountered in numerous geophysical flows, industrial safety…

Chaotic Dynamics · Physics 2007-05-23 Bernard J. Geurts

The effect of oscillatory shear flows on turbulent transport of passive scalar fields is studied by numerical computations based on the results provided by E. Kim [\emph{Physics of Plasmas}, {\bf 13}, 022308, 2006]. Turbulent diffusion is…

Plasma Physics · Physics 2009-11-13 A. P. L. Newton , E. Kim

We present a phenomenological model for the mixing length used in turbulence models. It has the advantage of naturally accounting for the object's geometry while satisfying the standard symmetries of the Navier-Stokes equations. We employ…

The dynamics of phase separation for a binary fluid subjected to a uniform shear are solved exactly for a model in which the order parameter is generalized to an n-component vector and the large-n limit taken. Characteristic length scales…

Statistical Mechanics · Physics 2009-10-31 N. P. Rapapa , A. J. Bray

The miscible displacement of a shear-thinning fluid by another of same rheological properties is studied experimentally in a transparent fracture by an optical technique imaging relative concentration distributions. The fracture walls have…

We report on a numerical study of the shear flow of a simple two-dimensional model of a granular material under controlled normal stress between two parallel smooth, frictional walls, moving with opposite velocities $\pm$V . Discrete…

Soft Condensed Matter · Physics 2012-10-15 Zahra Shojaaee , Jean-Noël Roux , François Chevoir , Wolf Dietrich

This article aims to make a detailed analysis of co-flowing plane Couette flows. Particularly, the variation of flow quantities from the turbulent to non-turbulent region is studied. While the enstrophy exhibits a sharp jump, the other…

Fluid Dynamics · Physics 2022-11-01 Manohar Teja Kalluri , Vagesh D. Narasimhamurthy

A major obstacle for the understanding of long electrical discharges is the complex dynamics of streamer coronas, formed by many thin conducting filaments. Building macroscopic models for these filaments is one approach to attain a deeper…

Plasma Physics · Physics 2017-05-10 A. Luque , M. González , F. J. Gordillo-Vázquez

Abrupt transition to turbulence may occur in pipe and channel flows at moderate flow rates, an unexpected event according to linear stability theory, and has been an open problem in fluid dynamics for more than a century. Extensive…

Fluid Dynamics · Physics 2017-10-09 Jianjun Tao , Xiangming Xiong

We study turbulent flows in planar channels with unstable thermal stratification, using direct numerical simulations in a wide range of Reynolds and Rayleigh numbers and reaching flow conditions which are representative of asymptotic…

Fluid Dynamics · Physics 2017-06-28 Sergio Pirozzoli , Matteo Bernardini , Roberto Verzicco , Paolo Orlandi

The turbulent flow of a fluid carrying trace amounts of a condensable species through a differentially cooled vertical channel geometry is simulated using single-phase direct numerical simulations. The release of latent heat during…

Fluid Dynamics · Physics 2020-01-28 Philipp Bahavar , Claus Wagner

We study compressible fluid flow in narrow two-dimensional channels using a novel molecular dynamics simulation method. In the simulation area, an upstream source is maintained at constant density and temperature while a downstream…

Condensed Matter · Physics 2009-10-22 M. Sun , C. Ebner

The competition between the drive and stabilization of plasma microinstabilities by sheared flow is investigated, focusing on the ion temperature gradient mode. Using a twisting mode representation in sheared slab geometry, the…

Plasma Physics · Physics 2015-05-19 Sarah L. Newton , Steve C. Cowley , Nuno F. Loureiro

The high dimensionality and complex dynamics of turbulent flows in urban street canyons present significant challenges for wind and environmental engineering, particularly in addressing air quality, pollutant dispersion, and extreme wind…

Fluid Dynamics · Physics 2025-01-24 Tomek Jaroslawski , Aakash Patil , Beverley McKeon

On its way to turbulence, plane Couette flow - the flow between counter-translating parallel plates - displays a puzzling steady oblique laminar-turbulent pattern. We approach this problem via Galerkin modelling of the Navier-Stokes…

Fluid Dynamics · Physics 2015-06-11 K. Seshasayanan , P. Manneville

Dense mixture of granules and liquid often shows a sever shear thickening and is called a dilatant fluid. We construct a fluid dynamics model for the dilatant fluid by introducing a phenomenological state variable for a local state of…

Soft Condensed Matter · Physics 2015-06-03 Hiizu Nakanishi , Shin-ichiro Nagahiro , Namiko Mitarai

Despite recent progress, laminar-turbulent coexistence in transitional planar wall-bounded shear flows is still not well understood. Contrasting with the processes by which chaotic flow inside turbulent patches is sustained at the local…

Fluid Dynamics · Physics 2017-12-15 Paul Manneville

Using event-driven molecular dynamics simulations, we quantify how the self diffusivity of confined hard-sphere fluids depends on the nature of the confining boundaries. We explore systems with featureless confining boundaries that treat…

Soft Condensed Matter · Physics 2015-05-30 William P. Krekelberg , Vincent K. Shen , Jeffrey R. Errington , Thomas M. Truskett