- Volume 16 Issue 2
This study presents computational analyses for low-drag aerodynamic design that are applied to modify a long-endurance UAV. EAV-2 is a test-bed for a hybrid electric power system (fuel cell and solar cell) that was developed by the Korean Aerospace Research Institute (KARI) for use in future long-endurance UAVs. The computational investigation focuses on designing a wing with a reduced drag since this is the main contributor of the aerodynamic drag. The airfoil and wing aspect ratio of the least drag are defined, the fuselage configuration is modified, and raked wingtips are implemented to further reduce the profile and induced drag of EAV-2. The results indicate that the total drag was reduced by 54% relative to EAV-1, which was a small-sized version that was previously developed. In addition, static stabilities can be achieved in the longitudinal and lateral-directional by this low-drag configuration. A long-endurance flight test of 22 hours proves that the low-drag design for EAV-2 is effective and that the average power consumption is lower than the objective cruise powerof 200 Watts.
Long Endurance;UAV;CFD;Low-Reynolds Airfoil;Drag Prediction
- B. H. Lee, P. M. Park, K. B. Kim, and B. J. Cha, "A Study on Optimum Takeoff Time of the Hybrid Electric Powered Systems for a Middle Size UAV," Journal of The Korean Society Aeronautical and Space Sciences, Vol. 40, No. 11, 2012, pp. 940-947. https://doi.org/10.5139/JKSAS.2012.40.11.940
- FAI Record ID No. 16052, Federation Aeronautique Internationale.
- R. Laurenzo, "Soaring on a Solar Impulse," Aerospace America, Vol. 47, No. 5, 2009, pp. 32-36.
- P. M. Park, K. B. Kim, and B. J. Cha, "Flight Test of Hybrid Propulsion System for Electrically Powered UAV," Journal of the Korean Society of Propulsion Engineers, Vol. 17, No. 4, 2013, pp. 49-55. https://doi.org/10.6108/KSPE.2013.17.4.049
- W. J. Jin, Y. G. Lee, C. W. Kim, S. M. Ahn, and D. S. Lee, "Computational Analysis of Aerodynamic Performance of a small-scale Electric Aerial Vehicle," Proceeding of the 2010 Korean Society for Aeronautical & Space Sciences (KSAS) Fall Conference, Vol. 1, 2010, pp. 473-476.
- Y. G. Lee, W. J. Jin, S. M. Ahn, and D. S. Lee, "Numerical and In-Flight Drag Estimation of a Small Electric Aerial Vehicle," Proceeding of the 2011 Korean Society for Aeronautical & Space Sciences (KSAS) Spring Conference, Vol. 1, 2011, pp. 839-844.
- M. S. Selig, J. J. Guglielmo, A. P. Broeren, and P. Giguere, Summary of Low-Speed Airfoil Data, Vol. 1, Soar Tech Publications, Virginia Beach, 1995.
- C. A. Lyon, A. P. Broeren, P. Giguere, A. Gopalarathnam, and M. S. Selig, Summary of Low-Speed Airfoil Data, Vol. 3, Soar Tech Publications, Virginia Beach, 1998.
- ANSYS FLUENT Ver. 12 Software Package, Ansys Fluent Inc., Canonsburg, PA, USA.
- GAMBIT Software Package, Ver. 2.4.6, Ansys Fluent Inc., Canonsburg, PA, USA.
- TGRID Ver. 3.5, Ansys Fluent Inc., Canonsburg, PA, USA.
- G. W. Stickle, and J. L. Crigler, Propeller Analysis from Experimental Data, NACA Technical Report-712, 1941.
- Advanced Aircraft Analysis Software Package, Ver. 3.2, DARCorporation, Lawrence, KS, USA.
- W. J. Jin, and Y. G. Lee, "Computational Analysis of the Aerodynamic Performance of a Long-Endurance UAV," International Journal of Aeronautical and Space Sciences, Vol. 14, No. 4, 2014, pp. 374-382.
- H. H. Heyson, G. D. Riebe, and C. L. Fulton, Theoretical Parametric Study of the Relative Advantages of Winglets and Wing-tip Extension, NASA Technical Paper, 1977.
- R. Babigian, and S. Hayashibara, "Computational Study of the Vortex Wake Generated by a Three-Dimensional Wing with Dihedral, Taper, and Sweep," AIAA Paper 2009-4107, Jun. 2009.
- "Drag and Pressure Recovery Characteristics of Auxiliary Inlets at Subsonic Speeds," ESDU International PLC, London, UK, 1986.
- D. P. Raymer, Aircraft Design: A Conceptual Approach, the 4th edition, AIAA Education Series, AIAA Inc., Reston, 2006.
- P. M. Park, O. S. Hwang, Y. M. Kim, C. T. Kim, and K. J. Kwon, "Wind Tunnel Test on Propellers for Middle Size Electric Propulsion UAV," Proceeding of the 2011 Korean Society of Propulsion Engineers (KSPE) Fall Conference, Vol. 1, 2011, pp. 784-788.
- M. Drela, and H. Youngren, XFOIL 6.94 User Guide, Massachusetts Institute of Technology, Cambridge, MA, URL: http://web.mit.edu/drela/Public/web/xfoil/, 2001.
- Wing Design Optimization for a Long-Endurance UAV using FSI Analysis and the Kriging Method vol.17, pp.3, 2016, https://doi.org/10.5139/IJASS.2016.17.3.423
- Aerodynamic Design of the Solar-Powered High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) vol.17, pp.1, 2016, https://doi.org/10.5139/IJASS.2016.17.1.132
- Procedure for Determining Operation Limits of High-Altitude Long-Endurance Aircraft Under Icing Conditions vol.55, pp.1, 2018, https://doi.org/10.2514/1.C034490
Supported by : Korea Aerospace Research Institute (KARI)