Hostname: page-component-84b7d79bbc-g78kv Total loading time: 0 Render date: 2024-07-28T21:14:38.638Z Has data issue: false hasContentIssue false
  • English
  • Français

Investigation of unsteady aerodynamics effects in cycloidal rotor using RANS solver

Published online by Cambridge University Press:  10 May 2016

Y. Hu ,
F. Du  and
H. L. Zhang
Y. Hu*
Affiliation:
School of Aeronautics, Northwestern Polytechnic University, Xi'an, Shan Xi, 710072, China
F. Du
Affiliation:
School of Aeronautics, Northwestern Polytechnic University, Xi'an, Shan Xi, 710072, China
H. L. Zhang
Affiliation:
School of Aeronautics, Northwestern Polytechnic University, Xi'an, Shan Xi, 710072, China
Get access Rights & Permissions [Opens in a new window]

Abstract

The cycloidal propeller for a Micro-Aerial Vehicle (MAV)-scale cyclogyro in hover was studied using a 2D Reynolds-averaged Navier-Stokes equations solver. The effects of the blade dynamic stall, parallel Blade Vortex Interaction (BVI), inflow variation and flow curvature were discussed, based on the results of numerical simulation. The results from the 2D Computational Fluid Dynamics simulation indicated that the blade of the cycloidal rotor is actually performing a pitching oscillation, if observed in a moving reference frame. The dynamic stall vortices shed from the upstream blade cause intense parallel BVI on the downstream blade. The interaction will induce upwash and downwash on the downstream blade. This changes the effective reduced frequency and actually delays the stall of the blade, which is beneficial to the thrust generation. There is also strong downwash in the rotor cage and it changes the inflow velocity experienced by the blade. The downwash and flow curvature can either be beneficial or harmful to the thrust generation. The combined effects of dynamic stall, parallel BVI, inflow variation and flow curvature cause large aerodynamic force peaks and ensure the cycloidal rotors work at very low rotation speeds with high thrust. This guarantees that the cycloidal rotors possess at least the same level of hover efficiency as screw propellers.

Keywords

cycloidal propellerMicro-Aerial Vehicle (MAV)dynamic stallincompressible flows (low mach number)aircraft design
Type
Research Article
Information
The Aeronautical Journal , Volume 120 , Issue 1228 , June 2016 , pp. 956 - 970
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.Iosilevskii, G. and Levy, Y. Aerodynamics of the cyclogiro, 33rd AIAA Fluid Dynamics Conference and Exhibit, AIAA 2003-3473, 2003, Orlando, Florida, US.CrossRefGoogle Scholar
2.Iosilevskii, G. and Levy, Y.Experimental and numerical study of cyclogiro aerodynamics, AIAA J, 2006, 44, (12), pp 2866–2870.Google Scholar
3.Kim, S.J., Yun, C.Y. and Kim, D. Design and performance tests of cycloidal propulsion systems, 44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, AIAA 2003-1786, 2003, Norfolk, Virginia, US.CrossRefGoogle Scholar
4.Hwang, I.S., Min, S.Y., Kim, M.K.et al. Multidisciplinary optimal design of cyclocopter blade system, 46th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, AIAA 2005-2287, 2005, Austin, Texas, US.Google Scholar
5.Hwang, I.S., Hwang, C.S. and Kim, S.J. Structural design of cyclocopter blade system, 46th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, AIAA 2005-2020, 2005, Austin, Texas, US.Google Scholar
6.Hwang, I.S., Min, S.Y. and Lee, C.H. Experimental investigation of VTOL UAV cyclocopter with four rotors, 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, AIAA-2007-2247, 2007Google Scholar
7.Kim, S.J., Hwang, I.S. and Lee, H.Y. Design and development of unmanned VTOL cyclocopter, Symposium on Aerospace Science and Technology Proceedings, 12-14 August 2004, North Carolina, US.Google Scholar
8.Hwang, I.S., Min, S.Y. and Lee, C.H.Development of a four-rotor cyclocopter, J Aircr, 2008, 45, (6), pp 2151–2157.CrossRefGoogle Scholar
9.Benedict, M., Chopra, I., Ramasamy, M. and Leishman, J.G. Experimental investigation of the cycloidal rotor for a hovering micro air vehicle, Proceedings of the 64th Annual National Forum of the American Helicopter Society, 28-30 April 2008, Montreal, Canada.Google Scholar
10.Benedict, M., Chopra, I., Ramasamy, M. and Leishman, J.G. Experiments on the optimization of the MAV-scale cycloidal rotor characteristics towards improving their aerodynamic performance, Proceedings of the International Specialists Meeting on Unmanned Rotorcraft, 20-22 January 2009, Scottsdale, Arizona, US.Google Scholar
11.Moble Benedict and Inderjit Chopra. Aeroelasticanalysis of a MAV-scale cycloidal rotor, Proceedings of the 51st AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, AIAA 2010-2888, 12-15 April 2010, Orlando, Florida, US.CrossRefGoogle Scholar
12.Moble Benedict, Manikandan Ramasamy and Inderjit Chopra. Improving the aerodynamic performance of micro-air-vehicle-scale cycloidal rotor: An experimental approach, J Aircr, 2010, 47, (4), pp 1117–1125.Google Scholar
13.Benedict, M., Gupta, R. and Chopra, I. Design, development and flight testing of a twin-rotor cyclocopter micro air vehicle, Proceedings of the 67th Annual National Forum of the American Helicopter Society, 2011, Virginia Beach, Virginia, US.Google Scholar
14.Yang, K. Aerodynamic Analysis of an MAV-scale Cycloidal Rotor System Using a Structured Overset RANS Solver, Thesis for the Degree of Master of Science, University of Maryland, 2010.Google Scholar
15.Norton, R.L.Design of Machinery, 3rd ed, 2004, McGraw Hill.Google Scholar
16.Wang, S., Ingham, D.B. and Ma, L.Numerical investigation on dynamic stall of low Reynolds number flow around oscillating airfoils, Computers and Fluids, 2010, 39, pp 1529–1541.Google Scholar
17.Nobile, R. and Vahdati, M. Dynamic stall for a vertical axis wind turbine in a two-dimensional study, World Renewable Energy Congress 2011, 8-13, May 2011, Sweden,.CrossRefGoogle Scholar
18.McNaughton, J., Billard, F. and Revell, A.Turbulence modelling of low Reynolds number flow effects around a vertical axis turbine at a range of tip-speed ratios, Journal of Fluids and Structures, May 2014, 47, pp 124–138.Google Scholar
19.Fluent I. Fluent 6.3 user's guide, Fluent documentation.Google Scholar
20.Leishman, J.G.Principles of Helicopter Aerodynamics, 2nd ed, 2000, Cambridge University Press.Google Scholar