Results 261 to 270 of about 96,065 (304)

One-dimensional turbulence: model formulation and application to homogeneous turbulence, shear flows, and buoyant stratified flows

Journal of Fluid Mechanics, 1999
A stochastic model, implemented as a Monte Carlo simulation, is used to compute statistical properties of velocity and scalar fields in stationary and decaying homogeneous turbulence, shear flow, and various buoyant stratified flows. Turbulent advection is represented by a random sequence of maps applied to a one-dimensional computational domain ...
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Convective and Shear Flow Turbulence with Rotation

1992
As an introduction to this section we present an extension of the discussion of Mory [1] to include a case of more general geophysical significance, where the source of the initial turbulent motion is a natural one rather than the rather artificial case of turbulence generated by an oscillating grid.
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Fractals, Chaos, and Intermittency in Turbulent Shear Flows

Chaos in Heat Transfer and Fluid Dynamics, 1994
Abstract The fractal dimensions for fine scale turbulent velocity fields are estimated in two different ways: (1) from the Kolmogorov constant, μ, and (2) from the kurtosis of the velocity derivative. The fractal dimensions, D, are estimated to be in the range 2.45 ≤ D ≤ 2.73 which is comparable to previous investigations.
George D. Catalano, Julie A. Mathis, Keun S. Chang   +2 more
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Flow Visualization of Karman Vortex in Shear and Turbulent Flow

1992
Karman vortex velocimeter and flowmeter by use of laser diode have been developed in our laboratory 1).2). However the effects from such as shear flow, turbulent flow, channel wall and etc. are little known. In fact, the frequency of the Karman vortex in the shear flow which was measured by the method developed in our study was lower than that of the ...
S. Saito, M. Hashimoto, Y. Higuchi
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E×B shear flows and electromagnetic gyrofluid turbulence

Physics of Plasmas, 2000
Low frequency tokamak edge turbulence is modelled numerically using gyrofluid equations for electrons and ions on an equal footing. The electrons are electromagnetic, and arbitrarily strong finite gyroradius effects are included for the ions. Computations are in a globally consistent truncation of flux surface geometry arising from ideal tokamak ...
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Turbulence and shear stress measurements in hypersonic flow

16th Aerodynamic Ground Testing Conference, 1990
An assessment has been made of the potential for hot wire and laser anemometer measurements of turbulent fluctuations in hypersonic flow fields. The results of laser velocimeter experiments conducted in two hypersonic wind tunnels are reported and comparisons made with previous hot wire turbulence measurements.
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Interaction of monopoles, dipoles, and turbulence with a shear flow

Physics of Fluids, 2016
Direct numerical simulations have been conducted to examine the evolution of eddies in the presence of large-scale shear flows. The numerical experiments consist of initial-value-problems in which monopolar and dipolar vortices as well as driven turbulence are superposed on a plane Couette or Poiseuille flow in a periodic two-dimensional channel.
V. H. Marques Rosas Fernandes, L. P. J. Kamp, G. J. F. van Heijst, H. J. H. Clercx   +3 more
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Turbulence and mixing in a stratified shear flow

Geophysical & Astrophysical Fluid Dynamics, 1991
Abstract The characteristics of turbulence in the upper mixed layer and the nature of the sheared density interface of a two-fluid system, with a driven upper layer and a stagnant lower layer, were studied experimentally. The experiments were performed in a recirculating water channel and the mean flow in the upper layer was generated using a disk pump.
P. W. Stephenson, H. J. S. Fernando
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Large Scale Motions and Shear Stress Fluctuations in Turbulent Shear Flow

Volume 1A: Symposia, Part 2, 2015
We simultaneously measured the flow field and wall shear stress in a straight pipe and behind an orifice by means of particle image velocimetry (PIV) and the limiting diffusion current technique (LDCT), respectively[1]. The spatio-temporal correlation coefficients of the local vertical velocity and the shear stress fluctuations are presented, and the ...
Hinori Ito, Tatsuya Tsuneyoshi, Shan Feng, Takahiro Ito, Yoshiyuki Tsuji, Yuya Hideki   +5 more
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Vortical Structures in Transitional and Turbulent Shear Flows

2006
While in Chap. 10 we focused on the instability and breakdown of axial vortices, in this chapter we turn to the instability of shear layers, both free and wall-bounded. Unlike axial vortices, however, shear-flow transition from laminar to turbulent and fully developed turbulent shear flows have been the main field of turbulence and investigated much ...
Jie-Zhi Wu, Hui-Yang Ma, Ming-De Zhou
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