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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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References

1. Fang, F. and Chen, J.C. Experimental and analytical evaluation of flow in a square-to-square wind tunnel contraction, J Wind Engineering and Industrial Aerodynamics, 2001, 89, pp 247–262.Google Scholar
2. Chmielewski, G.E. Boundary layer considerations in the design of aerodynamic contractions, August 1974, 11, (8), McDonnell Douglas Research Laboratories, St Louis, MO.Google Scholar
3. Soltani, M.R., Ghorbanian, K., Mirzaei, M. and Dehghan Manshadi, M. Improvement of pressure distribution in the contraction of a wind tunnel due to turbulence reduction, 2008, SHARIF J Science & Techn, under review.Google Scholar
4. Lanspeary, P.V. and Bull, M.K. A mechanism for laminar three dimensional separation in duct contractions, 1998, 13th Australasian Fluid Mechanics Conference, 13-18 December, 1998, Monash University, Melbourne.Google Scholar
5. Bottcher, J. and Wedemeyer, E. The flow downstream of screens and its influence on the flow in the stagnation region of cylindrical bodies, J Fluid Mech, 1989, 204, pp 501–522.Google Scholar
6. Sonada, T. and Aihara, Y. Effects of pressure gradient on the secondary instability of Gortler vortices, 1981, AIAA Paper 81-0197.Google Scholar
7. Bansod, P. and Bradshaw, P. The flow in S-shaped ducts, Aeronaut Q, 1972, 23, (2), pp 131–140.Google Scholar
8. Takagi, S., Nishizawa, A. and Tokugawa, N. Observation of Gortler vortices in wind-tunnel contraction boundary layer, 2000, Third International Symposium on Turbulence, Heat and Mass Transfer, pp 275–282.Google Scholar
9. Takagi, S. and Tokugawa, N., Laminar-turbulent transition along the contraction nozzle in subsonic flow, 1999, 37th AIAA Aerospace Sciences Meeting and Exhibition, January 11-14 1999, Japan, 99-0279.Google Scholar
10. Nishizawa, A., Takagi, S. and Tokugawa, N. Rebirth of turbulence in laminarized boundary layers along the wind-tunnel contraction, 2001, 39th Aerospace Sciences Meeting and Exhibition, January 2001, Reno, NV.Google Scholar
11. Soltani, M.R., Dehghan Manshadi, M and Mirabdollahi, M.J. Flow quality study in a subsonic wind tunnel, 2004, ISME 2004 Conference, Tehran, Iran.Google Scholar
12. Soltani, M.R., Dehghan Manshadi, M. and Mirabdollahi, M.J. An experimental study of the flow characteristics in a subsonic wind tunnel, 2004, International Mechanical Engineering Conference, December 5-8, 2004, Kuwait.Google Scholar
13. Dehghan Manshad, M., Mirzaei, M., Soltani, M.R and Ghorbanian, K. Control of pressure gradient in the contraction of a wind tunnel, Proceedings of World Academy of Science, Engineering and Technology, 30, pp 261–266.Google Scholar