scispace - formally typeset
Journal ArticleDOI

Criteria for the selection of stochastic models of particle trajectories in turbulent flows

David J. Thomson
- 01 Jul 1987 - 
- Vol. 180, Iss: -1, pp 529-556
TLDR
In this paper, the relationships between the various criteria are examined for a very general class of models and it is shown that most of the criteria are equivalent and also how a model can be designed to satisfy these criteria exactly and to be consistent with inertial-subrange theory.
Abstract
Many different random-walk models of dispersion in inhomogeneous or unsteady turbulence have been proposed and several criteria have emerged to distinguish good models from bad. In this paper the relationships between the various criteria are examined for a very general class of models and it is shown that most of the criteria are equivalent. It is also shown how a model can be designed to satisfy these criteria exactly and to be consistent with inertial-subrange theory. Some examples of models that obey the criteria are described. As an illustration some calculations of dispersion in free-convective conditions are presented.

read more

Citations
More filters
Journal ArticleDOI

Particle transport in a random velocity field with Lagrangian statistics

Piero Olla
- 15 Nov 2002 - 
TL;DR: The transport properties of a random velocity field with Kolmogorov spectrum and time correlations defined along Lagrangian trajectories are analyzed, and a preference of the solid particle to lie in less energetic regions of the flow is observed.

On the quality assurance of surface energy flux measurements

Abstract: The fact that micrometeorological measurements of energy exchange processes at the surface are often not able to close the energy balance (Foken & Oncley 1995) motivated us to address the issue of quality assurance of these surface energy flux measurements. We concentrated on three parts of this issue: the determination of turbulent heat fluxes with their corrections and quality tests, footprint model based quality assessment for the turbulent heat fluxes, and methods to measure the ground heat flux. All data within this study were measured during the LITFASS-2003 field campaign (Beyrich et al., 2004). Our own work does not go deeper into radiation measurements, but we referred to the BSRN recommendations which represent a good standard (Gilgen et al., 1994).
Dissertation

Development of the PDF kinetic approach for modelling inertial particle dispersion in turbulent boundary layers

Andrew Bragg
TL;DR: In this article, the authors used probability density function (PDF) kinetic equations to model the dispersion of inertial particles in turbulent boundary layers, and developed new closure models which are non-local and attempt to take into account the effects of turbulence inhomogeneity, anisotropy and particle-wall collisions on dispersion tensors.
References
More filters
Journal ArticleDOI

Turbulence Structure in the Convective Boundary Layer

TL;DR: In this paper, a boundary layer experiment conducted over a flat site in northwestern Minnesota is discussed, where wind and temperature fluctuations near the ground were measured with AFCRL's fast-response instrumentation on a 32 m tower with MRU probes attached at five different heights to the tethering cable of a 1300 m2 kite balloon.
Book

Theory and Applications of Stochastic Differential Equations

TL;DR: Presents theory, sources, and applications of stochastic differential equations of Ito's type; those containing white noise; and the role of partial differential equations in this context.
Related Papers (5)