Ordered roughness effects on NACA 0026 airfoil

Zambri Harun, A. A. Abbas, R. Mohammed Dheyaa, M. I. Ghazali

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The effects of highly-ordered rough surface - riblets, applied onto the surface of a NACA 0026 airfoil, are investigated experimentally using wind tunnel. The riblets are arranged in directionally converging - diverging pattern with dimensions of height, h = 1 mm, pitch or spacing, s = 1 mm, yaw angle α = 0° and 10° The airfoil with external geometry of 500 mm span, 600 mm chord and 156 mm thickness has been built using mostly woods and aluminium. Turbulence quantities are collected using hotwire anemometry. Hotwire measurements show that flows past converging and diverging pattern inherit similar patterns in the near-wall region for both mean velocity and turbulence intensities profiles. The mean velocity profiles in logarithmic regions for both flows past converging and diverging riblet pattern are lower than that with yaw angle α = 0°. Converging riblets cause the boundary layer to thicken and the flow with yaw angle α = 0° produces the thinnest boundary layer. Both the converging and diverging riblets cause pronounced outer peaks in the turbulence intensities profiles. Most importantly, flows past converging and diverging pattern experience 30% skin friction reductions. Higher order statistics show that riblet surfaces produce similar effects due to adverse pressure gradient. It is concluded that a small strip of different ordered roughness features applied at a leading edge of an airfoil can change the turbulence characteristics dramatically.

Original languageEnglish
Article number012005
JournalIOP Conference Series: Materials Science and Engineering
Volume152
Issue number1
DOIs
Publication statusPublished - 31 Oct 2016

Fingerprint

Airfoils
Turbulence
Surface roughness
Boundary layers
Higher order statistics
Skin friction
Aluminum
Pressure gradient
Wind tunnels
Wood
Geometry

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)

Cite this

Ordered roughness effects on NACA 0026 airfoil. / Harun, Zambri; Abbas, A. A.; Dheyaa, R. Mohammed; Ghazali, M. I.

In: IOP Conference Series: Materials Science and Engineering, Vol. 152, No. 1, 012005, 31.10.2016.

Research output: Contribution to journalArticle

Harun, Zambri ; Abbas, A. A. ; Dheyaa, R. Mohammed ; Ghazali, M. I. / Ordered roughness effects on NACA 0026 airfoil. In: IOP Conference Series: Materials Science and Engineering. 2016 ; Vol. 152, No. 1.
@article{04a9750f2ffb4ffd90140dff061b3c24,
title = "Ordered roughness effects on NACA 0026 airfoil",
abstract = "The effects of highly-ordered rough surface - riblets, applied onto the surface of a NACA 0026 airfoil, are investigated experimentally using wind tunnel. The riblets are arranged in directionally converging - diverging pattern with dimensions of height, h = 1 mm, pitch or spacing, s = 1 mm, yaw angle α = 0° and 10° The airfoil with external geometry of 500 mm span, 600 mm chord and 156 mm thickness has been built using mostly woods and aluminium. Turbulence quantities are collected using hotwire anemometry. Hotwire measurements show that flows past converging and diverging pattern inherit similar patterns in the near-wall region for both mean velocity and turbulence intensities profiles. The mean velocity profiles in logarithmic regions for both flows past converging and diverging riblet pattern are lower than that with yaw angle α = 0°. Converging riblets cause the boundary layer to thicken and the flow with yaw angle α = 0° produces the thinnest boundary layer. Both the converging and diverging riblets cause pronounced outer peaks in the turbulence intensities profiles. Most importantly, flows past converging and diverging pattern experience 30{\%} skin friction reductions. Higher order statistics show that riblet surfaces produce similar effects due to adverse pressure gradient. It is concluded that a small strip of different ordered roughness features applied at a leading edge of an airfoil can change the turbulence characteristics dramatically.",
author = "Zambri Harun and Abbas, {A. A.} and Dheyaa, {R. Mohammed} and Ghazali, {M. I.}",
year = "2016",
month = "10",
day = "31",
doi = "10.1088/1757-899X/152/1/012005",
language = "English",
volume = "152",
journal = "IOP Conference Series: Materials Science and Engineering",
issn = "1757-8981",
publisher = "IOP Publishing Ltd.",
number = "1",

}

TY - JOUR

T1 - Ordered roughness effects on NACA 0026 airfoil

AU - Harun, Zambri

AU - Abbas, A. A.

AU - Dheyaa, R. Mohammed

AU - Ghazali, M. I.

PY - 2016/10/31

Y1 - 2016/10/31

N2 - The effects of highly-ordered rough surface - riblets, applied onto the surface of a NACA 0026 airfoil, are investigated experimentally using wind tunnel. The riblets are arranged in directionally converging - diverging pattern with dimensions of height, h = 1 mm, pitch or spacing, s = 1 mm, yaw angle α = 0° and 10° The airfoil with external geometry of 500 mm span, 600 mm chord and 156 mm thickness has been built using mostly woods and aluminium. Turbulence quantities are collected using hotwire anemometry. Hotwire measurements show that flows past converging and diverging pattern inherit similar patterns in the near-wall region for both mean velocity and turbulence intensities profiles. The mean velocity profiles in logarithmic regions for both flows past converging and diverging riblet pattern are lower than that with yaw angle α = 0°. Converging riblets cause the boundary layer to thicken and the flow with yaw angle α = 0° produces the thinnest boundary layer. Both the converging and diverging riblets cause pronounced outer peaks in the turbulence intensities profiles. Most importantly, flows past converging and diverging pattern experience 30% skin friction reductions. Higher order statistics show that riblet surfaces produce similar effects due to adverse pressure gradient. It is concluded that a small strip of different ordered roughness features applied at a leading edge of an airfoil can change the turbulence characteristics dramatically.

AB - The effects of highly-ordered rough surface - riblets, applied onto the surface of a NACA 0026 airfoil, are investigated experimentally using wind tunnel. The riblets are arranged in directionally converging - diverging pattern with dimensions of height, h = 1 mm, pitch or spacing, s = 1 mm, yaw angle α = 0° and 10° The airfoil with external geometry of 500 mm span, 600 mm chord and 156 mm thickness has been built using mostly woods and aluminium. Turbulence quantities are collected using hotwire anemometry. Hotwire measurements show that flows past converging and diverging pattern inherit similar patterns in the near-wall region for both mean velocity and turbulence intensities profiles. The mean velocity profiles in logarithmic regions for both flows past converging and diverging riblet pattern are lower than that with yaw angle α = 0°. Converging riblets cause the boundary layer to thicken and the flow with yaw angle α = 0° produces the thinnest boundary layer. Both the converging and diverging riblets cause pronounced outer peaks in the turbulence intensities profiles. Most importantly, flows past converging and diverging pattern experience 30% skin friction reductions. Higher order statistics show that riblet surfaces produce similar effects due to adverse pressure gradient. It is concluded that a small strip of different ordered roughness features applied at a leading edge of an airfoil can change the turbulence characteristics dramatically.

UR - http://www.scopus.com/inward/record.url?scp=84998723921&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84998723921&partnerID=8YFLogxK

U2 - 10.1088/1757-899X/152/1/012005

DO - 10.1088/1757-899X/152/1/012005

M3 - Article

AN - SCOPUS:84998723921

VL - 152

JO - IOP Conference Series: Materials Science and Engineering

JF - IOP Conference Series: Materials Science and Engineering

SN - 1757-8981

IS - 1

M1 - 012005

ER -