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Drag Reduction Design for a Long-endurance Electric Powered UAV

Jin, Wonjin;Lee, Yung-Gyo

  • Received : 2015.02.11
  • Accepted : 2015.05.29
  • Published : 2015.06.30

Abstract

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.

Keywords

Long Endurance;UAV;CFD;Low-Reynolds Airfoil;Drag Prediction

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Cited by

  1. 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
  2. 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
  3. 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

Acknowledgement

Supported by : Korea Aerospace Research Institute (KARI)