Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-17T08:19:27.920Z Has data issue: false hasContentIssue false

Experimental investigation of a helicopter rotor with Gurney flaps

Published online by Cambridge University Press:  24 January 2017

G. Gibertini*
Affiliation:
Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano, Milano, Italy
A. Zanotti
Affiliation:
Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano, Milano, Italy
G. Droandi
Affiliation:
Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano, Milano, Italy
F. Auteri
Affiliation:
Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano, Milano, Italy
G. Crosta
Affiliation:
Leonardo Helicopters, HSD Department, via G.Agusta 520, Cascina Costa di Samarate (VA), Italy

Abstract

The present work describes an experimental activity carried out to investigate the performance of Gurney flaps on a helicopter rotor model in hovering. The four blades of the articulated rotor model were equipped with Gurney flaps positioned at 95% of the aerofoil chord, spanning 14% of the rotor radius. The global aerodynamic loads and torque were measured for three Gurney flap configurations characterised by different heights. The global measurements showed an apparent benefit produced by Gurney flaps in terms of rotor performance with respect to the clean blade configuration. Particle image velocimetry surveys were also performed on the blade section at 65% of the rotor radius with and without the Gurney flaps. The local velocity data was used to complete the characterisation of the blade aerodynamic performance through the evaluation of the sectional aerodynamic loads using the the control volume approach.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2017 

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. Yeo, H. Assessment of active controls for rotor performance enhancement, J the American Helicopter Society, 2008, 53, (2), pp 152163.CrossRefGoogle Scholar
2. Chandrasekhara, M., Martin, P. and Tung, C. Compressible dynamic stall control using a variable droop leading edge airfoil, J Aircr, 2004, 41, pp 862869.CrossRefGoogle Scholar
3. Gardner, A., Richter, K., Mai, H. and Neuhaus, D. Experimental investigation of air jets to control shock-induced dynamic stall, J the American Helicopter Society, 2014, 59, (2), pp 111.CrossRefGoogle Scholar
4. Singh, C., Peake, D., Kokkalis, A., Khodagolian, V., Coton, F. and Galbraith, R. Control of rotorcraft retreating blade stall using air-jet vortex generators, J Aircr, 2006, 43, pp 11691176.CrossRefGoogle Scholar
5. Post, M. and Corke, T. Separation control using plasma actuators: Dynamic stall vortex control on oscillating airfoil, AIAA J, 2006, 44, pp 31253135.CrossRefGoogle Scholar
6. Feszty, D., Gillies, E. and Vezza, M. Alleviation of airfoil dynamic stall moments via trailing-edge flap flow control, AIAA J, 2001, 42, pp 1725.CrossRefGoogle Scholar
7. Dehaeze, F., Baverstock, K.D. and Barakos, G.N. CFD simulation of flapped rotors, Aeronautical J, 2015, 119, (1222), pp 15611583.CrossRefGoogle Scholar
8. Liebeck, R.H. Design of subsonic airfoils for high lift, J Aircr, 1978, 15, pp 547561.CrossRefGoogle Scholar
9. Kentfield, J.A.C. The potential of gurney flaps for improving the aerodynamic performance of helicopter rotors, AIAA International Powered Lift Conference, AIAA Paper 93-4883, 1-3 December 1993, Santa Clara, California, US.CrossRefGoogle Scholar
10. Pastrikakis, V.A., Steijl, R., Barakos, G.N. and Malecki, J. Computational aeroelastic analysis of a hovering W3 Sokol blade with Gurney flap, J Fluids and Structures, 2015, 53, pp 96111.CrossRefGoogle Scholar
11. Yee, K., Joo, W. and Lee, D.H. Aerodynamic performance analysis of a gurney flap for rotorcraft application, J Aircr, 2007, 44, pp 10031014.CrossRefGoogle Scholar
12. Woodgate, M.A., Pastrikakis, V.A. and Barakos, G.N. Method for calculating rotors with active gurney flaps, J Aircr, 2016, 53, (3), pp 605626.CrossRefGoogle Scholar
13. Li, Y., Wang, J. and Zhang, P. Influences of mounting angles and locations on the effects of Gurney Flaps, J Aircr, 2003, 40, (3), pp 494498.CrossRefGoogle Scholar
14. Maughmer, M.D. and Bramesfeld, G. Experimental investigation of gurney flaps, J Aircr, 2008, 45, pp 20622067.CrossRefGoogle Scholar
15. Chandrasekhara, M., Martin, P. and Tung, C. Compressible dynamic stall performance of a variable droop leading edge airfoil with a gurney flap, J American Helicopter Society, 2008, 53, pp 1825.CrossRefGoogle Scholar
16. Zanotti, A., Grassi, D. and Gibertini, G. Experimental investigation of a trailing edge l-shaped tab on a pitching airfoil in deep dynamic stall conditions, Proceedings of the Institution of Mechanical Engineers, Part G: J Aerospace Engineering, 2014, 228, (12), pp 23712382.CrossRefGoogle Scholar
17. Biava, M., Campanardi, G., Gibertini, G., Grassi, D., Vigevano, L. and Zanotti, A. Wind tunnel open section characterization for rotorcraft tests, Proceedings of 38th European Rotorcraft Forum, 4-7 September 2012, Amsterdam, The Netherlands.Google Scholar
18. Anderson, J.D. Fundamentals of Aerodynamics, 2nd edn, McGraw-Hill, New York, 1991.Google Scholar
19. Anderson, J.D. Modern Compressible Flow with Historical Perspective, 3rd ed, 2003, McGraw-Hill, New York, New York, US.Google Scholar
20. Droandi, G., Zanotti, A. and Gibertini, G. Aerodynamic interaction between rotor and tilting wing in hovering flight condition, J the American Helicopter Society, 2015, 60, (4), pp 120.CrossRefGoogle Scholar
21. Droandi, G. and Gibertini, G. Aerodynamic shape optimisation of a proprotor and its validation by means of CFD and experiments, Aeronautical J, 2015, 119, (1220), pp 12231251.CrossRefGoogle Scholar
22. Ragni, D., van Oudheusden, B. and Scarano, F. 3D pressure imaging of an aircraft propeller blade-tip flow by phase-locked stereoscopic PIV, Experiments in Fluids, 2012, 52, (2), pp 463477.CrossRefGoogle Scholar
23. PIVTEC, PIVview 2c/3c, user manual, Tech. Rep. www.pivtec.com, 2010.Google Scholar
24. Raffel, M., Willert, C. and Kompenhans, J. Particle Image Velocimetry, A Practical Guide, 1998, Springer, Heidelberg, Germany.CrossRefGoogle Scholar
25. Zanotti, A., Ermacora, M., Campanardi, G. and Gibertini, G. Stereo particle image velocimetry measurements of perpendicular blade-vortex interaction over an oscillating airfoil, Experiments in Fluids, 2014, 55, (9), pp 113.CrossRefGoogle Scholar
26. De Gregorio, F., Pengel, K. and Kindler, K. A comprehensive PIV measurement campaign on a fully equipped helicopter model, Experiments in Fluids, 2012, 53, (1), pp 3749.CrossRefGoogle Scholar
27. van Oudheusden, B.W., Scarano, F., Roosenboom, E.W.M., Casimiri, E.W.F. and Souverein, L.J. Evaluation of integral forces and pressure fields from planar velocimetry data for incompressible and compressible flows, Experiments in Fluids, 2007, 43, (2), pp 153162.CrossRefGoogle Scholar
28. Ragni, D., Ashok, A., van Oudheusden, B.W. and Scarano, F. Surface pressure and aerodynamic loads determination of a transonic airfoil based on particle image velocimetry, Measurement Science and Technology, 2009, 20, pp 114.CrossRefGoogle Scholar
29. Biava, M. RANS Computations of Rotor/Fuselage Unsteady Interactional Aerodynamics, PhD Thesis, 2007, Politecnico di Milano.Google Scholar
30. Roe, P.L. Approximate riemann solvers, parameter vectors and difference schemes, J Computational Physics, 1981, 43, pp 357372.CrossRefGoogle Scholar
31. Venkatakrishnan, V. On the accuracy of limiters and convergence to steady state solutions, Proceedings of 31st AIAA Aerospace Science Meeting & Exhibit, 1993, Reno, Nevada, US.CrossRefGoogle Scholar
32. Jameson, A. Time dependent calculations using multigrid with applications to unsteady flows past airfoils and wings, Proceedings of 10th AIAA Computational Fluid Dynamics Conference, 1991, Honolulu, Hawaii, US.CrossRefGoogle Scholar
33. Hunt, J.C.R., Wray, A. and Moin, P. Eddies, stream, and convergence zones in turbulent flows, Tech. Rep. CTR-S88, 1988, Center for Turbulence Research Report, Stanford University, Stanford, California, US.Google Scholar