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Control of separation in the concave portion of contraction to improve the flow quality

Published online by Cambridge University Press:  03 February 2016

K. Ghorbanian ,
M. R. Soltani ,
M. D. Manshadi  and
M. Mirzaei
K. Ghorbanian
Affiliation:
Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran
M. R. Soltani
Affiliation:
Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran
M. D. Manshadi
Affiliation:
Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran
M. Mirzaei
Affiliation:
Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran
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Abstract

Subsonic wind tunnel experiments were conducted to study the effect of forced transition on the pressure distribution in the concave portion of contraction. Further more, the effect of early transition on the turbulence level in the test section of the wind tunnel is studied. Measurements were performed by installing several trip strips at two different positions in the concave portion of the contraction. The results show that installation of the trip strips, have significant effects on both turbulence intensity and on the pressure distribution. The reduction in the free stream turbulence as well as the wall static pressure distribution varied significantly with the location of the trip strip. The results confirm the significant impact of the tripped boundary layer on the control of adverse pressure gradient. The trip strip at X/L = 0.115 improves pressure distribution in contraction and reduces turbulence intensity in the test section, considerably.

Type
Research Article
Information
The Aeronautical Journal , Volume 113 , Issue 1141 , March 2009 , pp. 177 - 182
Copyright
Copyright © Royal Aeronautical Society 2009 

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