Abstract/Details

An improved diffusion model for second-moment closures derived from zero-mean-shear turbulence

Straatman, Anthony Gerald.   University of Waterloo (Canada) ProQuest Dissertations & Theses,  1996. NN09387.

Abstract (summary)

An examination of diffusion modelling in second-moment turbulence closures is presented. The main objectives of the present work are to gain a better understanding of the processes that are grouped into the net diffusive transport of Reynolds stresses, $D\sb{ij}$, and to develop an improved model for $D\sb{ij}$. The benchmark case of zero-mean-shear turbulence is used as a guide in this study. The analysis of zero-mean-shear turbulence shows that the pressure-velocity processes in $D\sb{ij}$ play a central role in establishing the anisotropy level in diffusive turbulence. Existing models for $D\sb{ij}$ based solely on the triple velocity correlation are shown to be inadequate in the diffusive limit. The improved $D\sb{ij}$ model is formulated to account for the pressure-velocity processes, and to be exact in the diffusive limit. The present validation verifies the integrity of the improved model, and shows that including he influence of the pressure-velocity processes in a $D\sb{ij}$ model extends the model's range of applicability from the diffusive limit to situations where diffusion is much less important.

Indexing (details)


Subject
Mechanical engineering
Classification
0548: Mechanical engineering
Identifier / keyword
Applied sciences
Title
An improved diffusion model for second-moment closures derived from zero-mean-shear turbulence
Author
Straatman, Anthony Gerald
Number of pages
209
Degree date
1996
School code
1141
Source
DAI-B 57/06, Dissertation Abstracts International
ISBN
978-0-612-09387-4
Advisor
Stubley, G. D.; Raithby, G. D.
University/institution
University of Waterloo (Canada)
University location
Canada -- Ontario, CA
Degree
Ph.D.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
NN09387
ProQuest document ID
304354147
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
https://www.proquest.com/docview/304354147