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
Direct numerical simulation of rotating turbulent duct flow
KTH, School of Engineering Sciences (SCI), Mechanics.
KTH, School of Engineering Sciences (SCI), Mechanics.ORCID iD: 0000-0002-9819-2906
KTH, School of Engineering Sciences (SCI), Mechanics.ORCID iD: 0000-0002-2711-4687
2006 (English)In: Journal of turbulence, ISSN 1468-5248Article in journal (Other academic) Submitted
Abstract [en]

A direct simulation of turbulent flow in a rotating square duct using a second-order finite-volume method was performed. The axis of rotation was normal to the direction of the mean flow in theduct. The simulations are performed at Red = 4400 and for Rod = 0 up to 0.77. The strong effect of rotation on both the mean axial and secondary flows is plainly exhibited. A linear increase in the magnitude of the secondary flow was found with increasing rate of rotation. Turbulence quantities are presented to shed some light on the role of the boundary layer structure on the resistance of theflow. The growth of large-scale secondary roll-cells in the axial direction is studied with reference totheir dependence on the rotation number. The case of turbulent flow in a rotating duct that has been tilted 45 degrees around the axis of the mean flow is presented to illustrate the importance of geometric constraints on the characteristics of the flow.

Place, publisher, year, edition, pages
2006.
National Category
Fluid Mechanics and Acoustics
Identifiers
URN: urn:nbn:se:kth:diva-5621OAI: oai:DiVA.org:kth-5621DiVA: diva2:10049
Note
QS 20120316Available from: 2006-04-27 Created: 2006-04-27 Last updated: 2012-03-16Bibliographically approved
In thesis
1. Analysis of laminar and turbulent flows with turbomachinery, biotechnology and biomechanical applications
Open this publication in new window or tab >>Analysis of laminar and turbulent flows with turbomachinery, biotechnology and biomechanical applications
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

The goal of this study was initially to gain a better understanding of the effects of rotation on turbulent flow in ducts. Knowledge concerning the influence of rotation on the structures of turbulence is of fundamental importance in many applications, e.g. centrifugal separators, turbines or cooling channels in rotating machinery, as well as meteorology and oceanography. Rapidly rotating duct flow is studied experimentally with rotation numbers in the interval [ 0, 1] . To achieve this, in combination with relatively high Reynolds numbers (5000 – 30000 based on the hydraulic radius), water was used as the working medium. The influence of the rotation on the pressure drop in the duct was investigated and suitable scalings of this quantity were studied. Due to questions that arose in the experimental study, two numerical studies were initiated. The first study probed the effect of rotation and geometrical configuration on the development length for turbulent flow, while the second comprised a direct numerical simulation of turbulent flow in a rotating duct. It is shown that while system rotation does not have a marked effect on the development length in a plane channel, the development length is substantially shortened in a duct.

Additional systems subject to rotation or curvature effects were studied. The laminar flow of fluid in a rotating PCR-cone was analysed analytically and numerically to understand the increased mixing and temperature homogenization. The flow field in the cone was described and the increased mixing was due to a strong boundary layer flow incited by Coriolis and buoyancy effects. Comparisons of the numerical simulations with experiments yielded good results.

A study to quantify the flow of blood in cerebral malformations using three-dimensional videodensitometry was performed. Data from experiments with an idealized flow phantom, as well clinical pathologies, showed that the proposed methodology in conjunction with clinical injection protocols can yield mean flux data with an error less than 20%. Protocol improvements are proposed.

Place, publisher, year, edition, pages
Stockholm: Mekanik, 2006
Series
Trita-MEK, ISSN 0348-467X ; 2006:06
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-3928 (URN)
Public defence
2006-05-05, Sal F2, Lindstedtsvägen 28, Stockholm, 13:30
Opponent
Supervisors
Available from: 2006-04-27 Created: 2006-04-27 Last updated: 2012-03-21

Open Access in DiVA

No full text

Other links

www2.mech.kth.se

Authority records BETA

Brethouwer, GeertJohansson, Arne V.

Search in DiVA

By author/editor
Mårtensson, GustafBrethouwer, GeertJohansson, Arne V.
By organisation
Mechanics
In the same journal
Journal of turbulence
Fluid Mechanics and Acoustics

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 104 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