Journal ArticleDOI
Low-Reynolds-number effects in a fully developed turbulent channel flow
TLDR
In this article, low-Reynolds-number effects are observed in the inner region of a fully developed turbulent channel flow, using data obtained either from experiments or by direct numerical simulations.Abstract:
Low-Reynolds-number effects are observed in the inner region of a fully developed turbulent channel flow, using data obtained either from experiments or by direct numerical simulations. The Reynolds-number influence is observed on the turbulence intensities and to a lesser degree on the average production and dissipation of the turbulent energy. In the near-wall region, the data confirm Wei and Willmarth's (1989) conclusion that the Reynolds stresses do not scale on wall variables. One of the reasons proposed to account for this behavior, namely, the 'geometry' effect or direct interaction between inner regions on opposite walls, was investigated in some detail by introducing temperature at one of the walls, both in experiment and simulation. Although the extent of penetration of thermal excursions into the opposite side of the channel can be significant at low Reynolds numbers, the contribution these excursions make to the Reynolds shear stress and the spanwise vorticity in the opposite wall region is negligible. In the inner region, spectra and cospectra of the velocity fluctuations u and v change rapidly with the Reynolds number, the variations being mainly confined to low wavenumbers in the u spectrum.read more
Citations
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Journal ArticleDOI
Local isotropy in turbulent boundary layers at high Reynolds number
TL;DR: In this paper, hot-wire measurements of the velocity fluctuations in the test-section-ceiling boundary layer of the 80×120 foot Full-Scale Aerodynamics Facility at NASA Ames Research Center, the world's largest wind tunnel, were taken to test the localisotropy predictions of Kolmogorov's universal equilibrium theory.
Journal ArticleDOI
Fully developed turbulent pipe flow: a comparison between direct numerical simulation and experiment
J. G. M. Eggels,F. Unger,M. H. Weiss,Jerry Westerweel,Ronald J. Adrian,Rainer Friedrich,Ftm Nieuwstadt +6 more
TL;DR: In this paper, the authors investigated the differences between fully developed turbulent flow in an axisymmetric pipe and a plane channel geometry, and compared the results obtained from a channel flow simulation.
Journal ArticleDOI
Large-eddy simulation of transition to turbulence in a boundary layer developing spatially over a flat plate
TL;DR: In this article, a filter-structure-function (FSF) model is proposed for the simulation of a quasi-incompressible boundary layer developing spatially over an adiabatic flat plate, with a low level of upstream forcing.
Journal ArticleDOI
Experimental and numerical study of a turbulent boundary layer with pressure gradients
TL;DR: In this article, an experimental and numerical study of a turbulent boundary layer with pressure gradients was conducted using the recent "fringe method" with its numerical advantages and good inflow quality.
Book
Large-Eddy Simulations of Turbulence
TL;DR: In this paper, it was shown that the total number of degrees of freedom necessary to represent the whole span of scales of a three-dimensional turbulent flow is of the order of R l 9/4 in three dimensions.
References
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Journal ArticleDOI
Turbulence statistics in fully developed channel flow at low reynolds number
TL;DR: In this article, a direct numerical simulation of a turbulent channel flow is performed, where the unsteady Navier-Stokes equations are solved numerically at a Reynolds number of 3300, based on the mean centerline velocity and channel half-width, with about 4 million grid points.
Book
The Structure of Turbulent Shear Flow
TL;DR: In this paper, the authors present a method to find the optimal set of words for a given sentence in a sentence using the Bibliogr. Index Reference Record created on 2004-09-07, modified on 2016-08-08
Journal ArticleDOI
Direct simulation of a turbulent boundary layer up to R sub theta = 1410
TL;DR: In this paper, the turbulent boundary layer on a flat plate, with zero pressure gradient, is simulated numerically at four stations between R sub theta = 225 and R sub tta = 1410.
Book ChapterDOI
The Turbulent Boundary Layer
TL;DR: In this article, the authors examined the effect of roughness on boundary layer characteristics and showed that the wall is aerodynamically smooth for a turbulent boundary layer if the roughness elements are so small as to be buried in the laminar sublayer.
Journal ArticleDOI
Measurements of the structure of the Reynolds stress in a turbulent boundary layer
S. S. Lu,William W. Willmarth +1 more
TL;DR: In this article, the velocity at the edge of the viscous sublayer is used as a detector signal for bursts and sweeps, and the scaling of the mean time interval between bursts with outer flow variables is confirmed.