Turbulent transport measurements in a heated boundary layer: Combined effects of free-stream turbulence and removal of concave curvature

Michael D. Kestoras, Terrence W. Simon

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Turbulence measurements for both momentum and heat transport are taken in a boundary layer over a flat, recovery wall downstream of a concave wall (R=0.97m). The boundary layer appears turbulent from the beginning of the concave wall and grows over the test wall with negligible streamwise acceleration. The strength of curvature at the bend exit, δ99.5/R, is 0.04. The free-stream turbulence intensity is ∼8% at the beginning of the curve and is nearly uniform at ∼4.5% throughout the recovery wall. Comparisons are made with data taken in an earlier study, in the same test facility, but with a low free-stream turbulence intensity (-0.6%). Results show that on the recovery wall, elevated free-stream turbulence intensity enhances turbulent transport quantities such as -uv and vt in most of the outer part of the boundary layer, but near-wall values of vt remain unaffected. This is in contrast to near-wall vt values within the curve which decrease when free-stream turbulence is increased. At the bend exit, decreases of -uv and vt due to removal of curvature become more profound when free-stream turbulence intensity is elevated, compared to low-TI behavior. Measurements in the core of the flow indicate that the high levels of cross transport of momentum over the upstream concave wall cease when curvature is removed. Other results show that turbulent Prandtl numbers over the recovery wall are reduced to -0.9 when free-stream turbulence intensity is elevated, consistent with the rise in Stanton numbers over the recovery wall.

Original languageEnglish (US)
Title of host publicationHeat Transfer; Electric Power; Industrial and Cogeneration
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Electronic)9780791878811
DOIs
StatePublished - 1995
EventASME 1995 International Gas Turbine and Aeroengine Congress and Exposition, GT 1995 - Houston, United States
Duration: Jun 5 1995Jun 8 1995

Publication series

NameProceedings of the ASME Turbo Expo
Volume4

Other

OtherASME 1995 International Gas Turbine and Aeroengine Congress and Exposition, GT 1995
CountryUnited States
CityHouston
Period6/5/956/8/95

Bibliographical note

Publisher Copyright:
Copyright © 1995 by ASME All Rights Reserved.

Fingerprint Dive into the research topics of 'Turbulent transport measurements in a heated boundary layer: Combined effects of free-stream turbulence and removal of concave curvature'. Together they form a unique fingerprint.

Cite this