Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Turbulence and scalar flux modelling applied to separated flows
KTH, Superseded Departments, Mechanics.
2004 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

The turbulen flow in an asymmetric diffuser has been en studied by the means of Reynold average Navier-Stokes equations with both differential and explict algebraic expressions to model the Reynolds stress tensor. Modifications to the differential stress model have been derived, using the inverse turbulence timescale to obtain the dissipation of turbuence kinetic energy. The explicit algebraic Reynolds stress model has been used in combination with a two-equation platform to close the system of equations. Modifications made to the transport equation for the inverse turbulence timescale has made it possible to substantially relax the deman on near-wall resolution of this quantity. The rapid growth wth present in the original formulation can be treated as an explicit function of the wall-normal distance. In order to use the new formulation for the transport equation, an equation has as been derived to obtain the shortest distance bettwee a point and the closest wall, regardles of the geometric complexity of the domain. An explicit algebraic expression to model the passive scalar flux vector has been investigated using a comparison with a standard eddy-diffusivity model in the asymmetric diffuser. Results show a substantial improvement of the complexity of the scalar field and scalar flux vector in sepaarated flows. Automated code generation has been used in all the above studies to generate versatile model testing tools for general two-dimensional geometries. Finite element formulations are used for these tools.

Place, publisher, year, edition, pages
Stockholm: Mekanik , 2004. , x, 39 p.
Series
Trita-MEK, ISSN 0348-467X ; 2004:16
Keyword [en]
Space and plasma physics, fluid physics, plasma physics, applied mechanics, aerospace
Keyword [sv]
Rymd- och plasmafysik
National Category
Fusion, Plasma and Space Physics
Identifiers
URN: urn:nbn:se:kth:diva-92OAI: oai:DiVA.org:kth-92DiVA: diva2:14911
Public defence
2004-12-17, sal Ds, Lindstedtsvägen 5, Stockholm, 10:00
Opponent
Supervisors
Available from: 2004-12-17 Created: 2004-12-17 Last updated: 2012-03-20

Open Access in DiVA

fulltext(1047 kB)1135 downloads
File information
File name FULLTEXT01.pdfFile size 1047 kBChecksum MD5
b275436ad193bf5e2f270cef7cbf096fbd75f3e7bbf5e85fdd5117cb657bc7b73600917b
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Gullman-Strand, Johan
By organisation
Mechanics
Fusion, Plasma and Space Physics

Search outside of DiVA

GoogleGoogle Scholar
Total: 1135 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 664 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf