scispace - formally typeset
Open AccessJournal ArticleDOI

Fluctuations and transport in a stirred fluid with a mean gradient

Reads0
Chats0
TLDR
The effective thermal diffusivity D* and the probability distribution of temperature fluctuations are measured in a stirred fluid across which a temperature gradient is maintained.
Abstract
The effective thermal diffusivity D* and the probability distribution of temperature fluctuations are measured in a stirred fluid across which a temperature gradient is maintained. A distinct mixing transition is observed for D* as a function of Reynolds number R. Above the transitions, the distribution is strongly non-Gaussian and approaches an exponential exp(-‖δT‖/βξ), where β is the local temperature gradient and ξ the correlation length.

read more

Content maybe subject to copyright    Report

Citations
More filters
Journal ArticleDOI

Passive Scalars in Turbulent Flows

TL;DR: In this article, the complex morphology of the scalar field is reviewed, and they are related to the intermittency problem and other aspects of passive scalar behavior such as spectrum, probability density function, flux, and variance are also addressed.
Journal ArticleDOI

High Rayleigh Number Convection

TL;DR: Turbulent convection exemplifies many of the startling aspects of turbulent flows that have been uncovered in the past two decades, but frequently exhibits a novel twist as discussed by the authors, as in the case of free shear flows, convection can organize into large-scale vortical structures, but these then react back in subtle ways on the boundary layers which ultimately sustain them.
Journal ArticleDOI

Simplified models for turbulent diffusion : theory, numerical modelling, and physical phenomena

TL;DR: In this paper, simple mathematical models for the turbulent diffusion of a passive scalar field are developed with an emphasis on the symbiotic interaction between rigorous mathematical theory (including exact solutions), physical intuition, and numerical simulations.
Journal ArticleDOI

Turbulent Mixing of a Passive Scalar

TL;DR: A series of recent numerical experiments with a Gaussian but multiscale velocity field have shown that the small scale properties of a passive scalar mixed by a turbulent velocity field show departures from Komogorov theory at least as prominent as for the velocity field as mentioned in this paper.
Journal ArticleDOI

The Transition to Strong Convection

TL;DR: In this paper, the power-law pickup of ensemble average precipitation as a function of column water vapor w occurs above a critical value wc whose temperature dependence is determined for layer-integrated tropospheric temperature or saturation value.
Related Papers (5)