Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-08T02:13:23.377Z Has data issue: false hasContentIssue false

Experimental investigation of flowfield over an iced aerofoil

Published online by Cambridge University Press:  18 May 2016

M.D. Manshadi*
Affiliation:
Department of Mechanical and Aerospace Engineering, Malekashter University of Technology, Isfahan, Iran
M.K. Esfeh
Affiliation:
School of Mechanical Engineering, Yazd University, Yazd, Iran

Abstract

Wind-tunnel measurements were used to study the characteristics of the unsteady separation bubbles on a NACA 0015 aerofoil with simulated two-dimensional leading-edge glaze ice accretions. The unsteadiness present in the iced-aerofoil flowfield was determined using measurements of the time-dependent aerofoil surface pressure distribution at Reynolds number of 1.0 × 106. Additionally, the unsteady flow features were investigated through the power spectrum of the stream-wise velocity fluctuations using a hot-wire anemometry. The results showed that the highest value of root-mean-square fluctuation of the surface pressure consistently occurred upstream of the mean shear-layer reattachment location. Spectral analysis of stream-wise velocity fluctuations near reattachment location revealed evidence of the regular frequency at Strouhal numbers of 0.5-0.63. Moreover, the low-frequency oscillations associated with shear-layer flapping was also identified in the wake velocity spectra on the order of 10 Hz that resulted in Strouhal numbers of 0.0186-021.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2016 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Busch, G., Broeren, A.P. and Bragg, M.B. Aerodynamic simulation of a horn-ice accretion on a subscale model, J Aircr, 2008, 45, (2), pp 604613.Google Scholar
2. Lynch, F. and Khodadoust, A. Effects of ice accretions on aircraft aerodynamics, Progress in Aerospace Sciences, 2001, 37, pp 669767.Google Scholar
3. Bragg, M.B., Khodadoust, A. and Spring, S.A. Measurements in a leading-edge separation bubble due to a simulated airfoil ice accretion, AIAA J, 1986, 30, (6), pp 14621467.Google Scholar
4. Gurbaki, H.M. and Bragg, M.B. Unsteady flowfield about an iced airfoil, 42th AIAA Aerospace Sciences Meeting & Exhibit, 5-8 January 2004, Reno, Nevada, US.Google Scholar
5. Jacobs, J.J. and Bragg, M.B. Two- and three-dimensional iced airfoil separation bubble measurements by particle image velocimetry, 45th AIAA Aerospace Sciences Meeting & Exhibit, 8-11 January, Reno, Nevada, US.Google Scholar
6. Jacobs, J.J. and Bragg, M.B. Particle image velocimetry measurements of the separation bubble on an iced airfoil, 24th AIAA Applied Aerodynamics Conference, 5-8 June 2006, San Francisco, California, US, 2006.Google Scholar
7. Deck, S. and Thorigny, P. Unsteadiness of an axisymmetric separating-reattaching flow: Numerical investigation, J Physics of Fluids, 2007, 19, 065103.CrossRefGoogle Scholar
8. Sigurdson, L.W. The structure and control of a turbulent reattaching flow, J Fluid Mechanics, 1995, 298, pp 139165.Google Scholar
9. Kiya, M.S., Shimizu, M. and Mochizuki, O. Sinusoidal forcing of a turbulent separation bubble, J Fluid Mechanics, 1997, 342, pp 119139.Google Scholar
10. Mirzaeia, M. Ardekani, M.A. and Doosttalab, M. Numerical and experimental study of flow field characteristics of an iced airfoil, J Aerospace Science and Technology, 2009, 13, pp 267276.Google Scholar
11. Cherry, N.J., Hillier, R. and Latour, M.E.M.P. Unsteady measurements in a separated and reattaching flow, J Fluid Mechanics, 1984, 144, pp 1346.Google Scholar
12. Driver, D.M., Seegmiller, H.L. and Marvin, J.G. Time-dependent behavior of a reattaching shear layer, AIAA J, 1987, 25, (7), pp 914919.Google Scholar
13. Eaton, J.K. and Johnston, J.P. Low frequency unsteadiness of a reattaching turbulent shear layer, Turbulent Shear Flows III, Third International Symposium on Turbulent Shear Flows, September 1981, University of California at Davis, US, pp 162–170.Google Scholar
14. Kiya, M. and Sasaki, K. Structure of a turbulent separation bubble, J Fluid Mechanics, 1983, 137, pp 83113.Google Scholar
15. Kiya, M. Shimizu, M. and Mochizuki, O. Sinusoidal forcing of a turbulent separation bubble. J Fluid Mechanics, 1997, 342, pp 119139.Google Scholar
16. Lee, I. and Sung, H.J. Multiple-arrayed pressure measurement for investigation of the unsteady flow structure of a reattaching shear layer, J Fluid Mechanics, 2002, 463, pp 377402.Google Scholar
17. Sigurdson, L.W. The structure and control of a turbulent reattaching flow, J Fluid Mechanics, September 1995, 298, pp 139165.Google Scholar
18. Zaman, K.B.M.Q. and Potapczuk, M.G. The low-frequency oscillation in the flow over a NACA 0012 airfoil with an ‘iced’ leading edge, NASA/TM-102018, June 1989.Google Scholar
19. Bragg, M.B., Broeren, A.P. and Blumenthal, L.A. Iced-airfoil aerodynamics, Journal of Progress in Aerospace Sciences, 2005, 41, pp 323362.Google Scholar
20. Harold, E. and Addy, J.R. Ice accretions and icing effects for modern airfoils, NASA Technical Reports Server, NASA/TP 2000-210031, April 2000.Google Scholar
21. Lee, S. and Bragg, M.B. Investigation of factors affecting iced-airfoil aerodynamics, J Aircraft, 2003, 40, (3), pp 499508.Google Scholar
22. Bynum, D.S., Ledford, R.L. and Smotherman, W.E. Wind tunnel pressure measuring techniques, AEDC-TR-70-250, 1970.Google Scholar
23. Barlow, J.B., William, H.R. and Pope, A. Low-Speed Wind Tunnel Testing, 3rd ed, 1999, John Wiley & Sons, New York, NY, US.Google Scholar
24. Soltani, M.R., Rasi, F., Seddighi, M. and Bakhshalipour, A. An experimental investigation of time lag in pressure-measuring systems, 2nd Ankara International Aerospace Conference, AIAC-2005-028, August 2005.Google Scholar
25. Jorgenson, F. How to Measure Turbulence with Hot-wire Anemometers (A Practical Guide), 2002, Dantec Dynamics, Skovlunde, Denmark.Google Scholar
26. Yavuzkurt, S. A guide to uncertainty analysis of hot-wire data, J Fluids Engineering, Jun 1984, 106, pp 181186.Google Scholar
27. Ansell, P.J. and Bragg, M.B. Measurement of unsteady flow reattachment on an airfoil with a leading-edge horn-ice shape, 30th AIAA Applied Aerodynamics Conference, 25-28 June 2012, New Orleans, Louisiana, US.Google Scholar
28. Broeren, A.P. and Bragg, M.B. Flowfield measurements about an airfoil with leading edge ice shapes, J Aircr, 2006, 43, (4), pp 12261243.Google Scholar
29. Gurbaki, H.M. Ice-Induced Unsteady Flowfield Effects on Airfoil Performance, Ph.D. Dissertation, University of Illinois at Urbana-Champaign, US, 2003.Google Scholar
30. Feng, K.E., Ying Zheng, L.I.U. and Han-Ping, C.H.E.N. Simultaneous flow visualisation and wall-pressure measurement of the turbulent separated and reattachment flow over a backward facing step, J Hydrodynamics, 2007, 19, (2), pp 180187.Google Scholar
31. Mabey, D.G. Analysis and correlation of data on pressure fluctuations in separated flow, J Aircr, 1972, 9, (9), pp 642645.Google Scholar
32. Heenan, A.F. and Morrison, J.F. Passive control of pressure fluctuations generated by separated flow, AIAA J, 1998, 36, (6), pp 10141022.Google Scholar
33. Ansell, P.J. Unsteady Modes in the Flowfield About an Airfoil with a Leading-Edge Horn-Ice Shape, 2013, Ph.D. Dissertation, University of Illinois at Urbana-Champaign, US.CrossRefGoogle Scholar