Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-05T08:57:44.500Z Has data issue: false hasContentIssue false

The influence of transition onset location on the performance of shock control bumps

Published online by Cambridge University Press:  27 January 2016

S. C. McIntosh
Affiliation:
Department of Mechanical Engineering, University of Sheffield, Sheffield, UK
N. Qin*
Affiliation:
Department of Mechanical Engineering, University of Sheffield, Sheffield, UK

Abstract

In order to investigate the robustness of three dimensional bumps on shock control for natural laminar-flow wings, the impact of transition onset location on the overall performance of the shock control device was studied. For a ramp bump, a moderate ramp start angle θr =4° was found to effectively fix the location of the leading leg of the shock lambda, decreasing chord-wise movement in the main shock position resulting from variations in transition onset location. With increasing transition onset length from xtrans =0% chord to 45% chord, little influence was found regarding the overall performance of the shock control device but a down-stream movement of the secondary leg of the shock lambda in a range about 3% chord was observed. Change in the boundary-layer displacement thickness due to varying transition onset locations was identified as the primary mechanism responsible for this secondary shock leg movement.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2013 

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

1. Joslin, R.D. Aircraft laminar-flow control, Annual Review of Fluid Mechanics, 1998, 30, pp 129.Google Scholar
2. Qin, N. and Monet, D. 3D Bumps for Transonic Wing Shock Control and Drag Reduction. CEAS Aerodynamics Research Conference, Cambridge, UK, June 2002.Google Scholar
3. Qin, N., Wong, W.S., Le Moigne, A. and Sellars, N. Validation and Optimisation of 3D Bumps for Transonic Wing Drag Reduction. CEAS/KATNet Confrence on Key Aerodynamic Technologies, June 2005.Google Scholar
4. König, B., PäTxold, M., Lutz, T. and Krämer, E. Shock control bumps on flexible and trimmed transport aircraft in transonic flow, New Results in Numerical and Experimental Fluid Mechanics VI, pp 8087, 2007.Google Scholar
5. Qin, N., Wong, W.S. and LeMoigne, A. Three-dimensional contour bumps for transonic wing drag reduction. Proceedings of the Institution of Mechanical Engineers, Part G: J Aerospace Engineering, 2008, 222, (5), pp 619629.Google Scholar
6. Ogawa, H., Babinsky, H., Pätzold, M. and Lutz, T. Shock-wave/boundary-layer interaction control using three-dimensional bumps for transonic wings, AIAA J, 2008, 46, pp 14421452.Google Scholar
7. Wong, W.S., Qin, N., Sellars, N., Holden, H. and Babinsky, H. A Combined experimental and numerical study of flow structures over three-dimensional shock control bumps, Aerospace Science and Technology, 2008, 12, (9), pp 436447.Google Scholar
8. Bruce, P.J.K. and Babinsky, H. Experimental study into the flow physics of three-dimensional shock control bumps. J Aircr, 2012, 49, pp 12221233.Google Scholar
9. Liu, X. and Squire, L.C. An investigation of shock/boundary-layer interactions on curved surfaces at transonic speeds, J Fluid Mechanics, 1988, 187, pp 467486.Google Scholar
10. Sommerer, A., Lutz, A.T. and Wagner, S. Numerical Optimisation of Adaptive Transonic Airfoils wih Variable Camber. In ICAS Congress, 2000.Google Scholar
11. Anders, S.G., Seller, W.L. and Washburn, A.E. Active Flow Control Activities at NASA Langley. In 2nd AIAA Flow Control Conference, 2004.Google Scholar