Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-03T02:22:39.787Z Has data issue: false hasContentIssue false
  • English
  • Français

CFD simulation of flapped rotors

Part of: 75 year anniversary of Aeronautical Engineering at Glasgow University

Published online by Cambridge University Press:  27 January 2016

F. Dehaeze ,
K. D. Baverstock  and
G. N. Barakos
F. Dehaeze*
Affiliation:
CFD Laboratory, School of Engineering, University of Liverpool, Liverpool, UK
K. D. Baverstock*
Affiliation:
AgustaWestland, Yeovil, UK
G. N. Barakos*
Affiliation:
CFD Laboratory, School of Engineering, University of Liverpool, Liverpool, UK
*
[email protected]
[email protected]
[email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The use of active trailing edge flaps on rotors may lead to performance benefits as well as noise and vibration reduction. In this work, computational fluid dynamics, using the HMB2 solver, is used to assess the effect of the trailing edge flaps on the whole flight domain of a modern main rotor. Starting from a baseline blade design, multiple techniques are demonstrated. The flap is first assessed using 2D pitching aerofoil simulations, followed by dMdt simulations, that account for the simultaneous variations of pitch and Mach around the azimuth. It was shown that enhanced lift was obtained while inspection of the moment coefficient showed negative damping for the flap for a limited set of conditions. Due to the 2D formulation, dMdt computations are fast to perform and can be used to inform codes predicting the rotor performance. The flap was then assessed in hover, and only allowed for limited improvement in blade performance at high thrust. In forward flight, the flap was actuated at a frequency of 1 per revolution, and was found to have a strong effect on the loads on the retreating side. The effect on the moments was even stronger. The flight envelope of the blade was explored, and clean and flapped cases were compared. The most noticeable changes occur at high and medium thrust. The CFD method was found to be efficient and robust, without any substantial penalties in CPU time, due to the flap modelling, over the tested conditions.

Type
Research Article
Information
The Aeronautical Journal , Volume 119 , Issue 1222: A Rotorcraft Special Issue , December 2015 , pp. 1561 - 1583
Copyright
Copyright © Royal Aeronautical Society 2015

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.Bae, E.S., Gandhi, F. and Maughmer, M.Optimally scheduled deployments of miniature Trailing-Edge Effectors for Rotorcraft Power Reduction, American Helicopter Society 65th Annual Forum, 27-29 May 2009, Grapevine, TX, USA.Google Scholar
2.Bae, E.S. and Gandhi, F.Upstream active Gurney fap for rotorcraft vibration reduction, American Helicopter Society 68th Annual Forum, 1-3 May 2012, Fort Worth, TX, USA.Google Scholar
3.Padthe, A.Simultaneous BVI noise and vibration reduction in rotorcraft using microflaps including the effect of actuator saturation, American Helicopter Society 68th Annual Forum, 1-3 May 2012, Fort Worth, TX, USA.Google Scholar
4.Bauchau, O., Min, B.-Y. and Sankar, L.A CFD-CSD coupled-analysis of HART-II rotor vibration reduction using Gurney flaps, American Helicopter Society 68th Annual Forum, 11-13 May 2010, Phoenix, AZ, USA.Google Scholar
5.Straub, F.K., Anand, V.R., Birchette, T.S. and Lau, B.H.SMART rotor development and wind tunnel test, 35th European Rotorcraft Forum, 22-25 September 2009, Hamburg, Germany, Paper No 1200.Google Scholar
6.Sim, B.W., Potsdam, M., Kitaplioglu, C., Lemasurier, P., Lorber, P. and Andrews, J.Localized, non-harmonic active fap motions for low frequency in-plane noise reduction, American Helicopter Society 68th Annual Forum, 1-3 May 2012, Fort Worth, TX, USA.Google Scholar
7.Birchette, T.S., Straub, F.K., Brouwers, E.W., Bussom, R.C. and Centolanza, L.R.Active flap design for an advanced CH-47, American Helicopter Society 69th Annual Forum, 21-23 May 2014, Phoenix, AZ, USA.Google Scholar
8.Samusenko, A., Esaulov, S. and Ivchin, V.A.Simulation of helicopter vibration reduction by means of higher harmonics control with the use of flight simulator, 38th European Rotorcraft Forum, 4-6 September 2012, Amsterdam, The Netherlands, Paper No 13.Google Scholar
9.Tamer, A., Muscarello, V., Masarati, P. and Quaranta, G.Helicopter vibratory loads and vibrations reduction using higher-harmonic control, 39th European Rotorcraft Forum, 3-5 September 2013, Moscow, Russia, Paper No 37.Google Scholar
10.Fogarty, D.E., Wilbur, M.L., Sekula, M.K. and Boyd, D.D.CFD/CSD investigation of BVI noise reduction using higher harmonic active-twist control, 38th European Rotorcraft Forum, 4-6 September 2012, Amsterdam, The Netherlands, Paper No 75.Google Scholar
11.Rabourdin, A., Maurice, J.-B., Dietrich, O. and Konstanzer, P.Blue pulse active rotor control at Airbus Helicopters – new EC-145 demonstrator & flight test results, American Helicopter Society 70th Annual Forum, 20-22 May 2013, Montréal, Québec.Google Scholar
12.Ravichandran, K., Chopra, I., Wake, B.E. and Hein, B.Trailing-edge faps for rotor performance enhancement and vibration control, J American Helicopter Soc, April 2013, 58, (2), pp 1–13.Google Scholar
13.Léon, O., Hayden, E. and Gandhi, F.Rotorcraft operating envelope expansion using extendable chord sections, American Helicopter Society 65th Annual Forum, 27-29 May 2009, Grapevine, TX, USA.Google Scholar
14.Barakos, G., Steijl, R., Badcock, K. and Brockelhurst, A.Development of CFD capability for full helicopter engineering analysis, 31st European Rotorcraft Forum, 13-15 September 2005, Florence, Italy.Google Scholar
15.Osher, S. and Chakravarthy, S.Upwind schemes and boundary conditions with applications to Euler equations in general geometries. J Computational Physics, January-February 1983, 50, pp 447–481.Google Scholar
16.van Leer, B.Towards the ultimate conservative difference scheme. V-A second-order sequel to Godunov’s method, J Computational Physics, July 1979, 32, pp 101–136.Google Scholar
17.van Albada, G.D., van Leer, B.B. and Roberts, W.W.A comparative study of computational methods in Cosmic Gas Dynamics, Astronomy and Astrophysics, April 1982, 108, (1), pp 76–84.Google Scholar
18.Menter, F.R.Two-equation eddy-viscosity turbulence models for engineering applications, AIAA J, 1994, 32 (8), pp 1598–1605.Google Scholar
19.Axelsson, O.Iterative Solution Methods, 1994, Cambridge University Press, Cambridge, MA, USA.Google Scholar
20.Tickel, B.Taking shape in 12.0, ANSYS Advantage, 2009, 3 (1), pp 8–10.Google Scholar
21.Steijl, R., Barakos, G. and Badcock, K.A framework for CFD analysis of helicopter rotors in hover and forward flight, Int J Numerical Methods in Fluids, 2006, 51 (8), pp 819–847.Google Scholar
22.Steijl, R., Woodgate, M. and Barakos, G.CFD Requirements for efficient smart-rotor analysis, 35th European Rotorcraft Forum, 16-18 September 2009, Hamburg, Germany, Paper No 1187.Google Scholar
23.Dehaeze, F. and Barakos, G.N.Mesh deformation method for rotor flows, J Aircr, January-February 2012, 49, (1), pp 82–92.Google Scholar
24.Goura, G.S.L., Badcock, K.J., Woodgate, M.A. and Richards, B.E.Implicit method for the time marching analysis of flutter, Aeronaut J, April 2001, 105, (1046), pp 199–214.Google Scholar
25.Blom, F.J.Considerations on the spring analogy, Int J Numerical Methods in Fluids, 2000, 32, pp 647–668.Google Scholar
26.Dubuc, L., Cantariti, F., Woodgate, M.A., Gribben, B., Badcock, K.J. and Richards, B.E.A grid deformation technique for unsteady flow computations, Int J Numerical Methods in Fluids, 2000, 32, pp 285–311.Google Scholar