Optimal Design of Airfoil with High Aspect Ratio in Unmanned Aerial Vehicles

Authors: Kyoungwoo Park, Ji-Won Han, Hyo-Jae Lim, Byeong-Sam Kim, Juhee Lee

Abstract:

Shape optimization of the airfoil with high aspect ratio of long endurance unmanned aerial vehicle (UAV) is performed by the multi-objective optimization technology coupled with computational fluid dynamics (CFD). For predicting the aerodynamic characteristics around the airfoil the high-fidelity Navier-Stokes solver is employed and SMOGA (Simple Multi-Objective Genetic Algorithm), which is developed by authors, is used for solving the multi-objective optimization problem. To obtain the optimal solutions of the design variable (i.e., sectional airfoil profile, wing taper ratio and sweep) for high performance of UAVs, both the lift and lift-to-drag ratio are maximized whereas the pitching moment should be minimized, simultaneously. It is found that the lift force and lift-to-drag ratio are linearly dependent and a unique and dominant solution are existed. However, a trade-off phenomenon is observed between the lift-to-drag ratio and pitching moment. As the result of optimization, sixty-five (65) non-dominated Pareto individuals at the cutting edge of design spaces that is decided by airfoil shapes can be obtained.

Keywords: Unmanned aerial vehicle (UAV), Airfoil, CFD, Shape optimization, Lift-to-drag ratio.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1077457

References:

[1] H. C. Hwang and K.J. Yoon, "2004 International MAV Competition and Analysis for the MAV Technologies", Journal of KSAS(Korean), 2004.
[2] S.A. Cambone, K.J. Krieg, P. Pace, and W. Linton, "Unmanned Aircraft Systems Roadmap 2005-2030," Office of the Secretary of Defense, 2005.
[3] D. Schawe, C.H. Rohardt, and G. Wichmann, "Aerodynamic design assessment of Strato 2C and its potential for unmanned high altitude airbone platforms," Aerospace Science and Technology No. 6, 2002, pp43-51.
[4] Z. Goraj, "Design challenges associated with development of a new generation UAV," Aircraft Engineering and Aerospace Technology: An International Journal, Vol. 77, No. 5, 2005, pp.361-368.
[5] T. G. Grabowski, A. Frydrychewicz, Z. Goraj and Suchodolski, "MALE UAV design of an increased reliability level," Aircraft Engineering and Aerospace Technology: An international Journal, Vol. 78, No. 3, 2006, pp 226-235.
[6] S. Painchaud-Ouellet, C. Tribues, J.Y. Trepanier, and D. Pelletier, "Airfoil Shape Optimization Using a Nonuniform Rational B-Splines Parametrization Under Thickness Constraint," AIAA Journal, Vol. 44, No. 10, 2006, pp. 2170-2178.
[7] D.J. Pines and F. Bohorquez,., "Challenges Facing Future Micro-Air- Vehicle Development," Journal of Aircraft, Vol. 43, No. 2, 2006, pp.290-305.
[8] T.T.H. Ng and G.S.B. Leng, "Application of genetic algorithms to conceptual design of a micro-air-vehicle," Engineering Applications of Artificial Intelligence, Vol 15, 2002, pp439-445.
[9] A.S. Fraser, "Simulation of genetic systems," Journal of Theoretical Biology, 1962, pp. 329-349.
[10] J.H. Holland, Adaptation in Natural and Artificial Systems: an Introductory Analysis with Applications to Biology, Control, and Artificial Intelligence, MIT Press, Cambridge, 1975.
[11] D. Goldberg, Genetic Algorithms in Search, Optimization and Machine Learning, Addision-Wesley, 1989.
[12] A.C. Poloni, A. Giurgevich, L. Onesti, and V. Pediroda, "Hybridization of a Multi-Objective Genetic Algorithm, a Neural Network and a Classical Optimizer for a Complex Design Problem in Fluid Dynamics", Dipartimento di Energetica Universita di Trieste, Italy, 1999.
[13] L.B. Booker, Improving Search in Genetic Algorithms," in Davis L (Editor), Genetic Algorithms and Simulated Annealing, Morgan Kaufmann Publishers, Los Altos, CA 1987.
[14] J. Lee, S. Lee, and K. Park, "Global Shape Optimization of Airfoil Using Multi-Objective Genetic Algorithm," Transaction of KSME B, Vol. 29. No. 10, 2005, pp. 1163-1171.
[15] STAR-CD v3.20 Methodology, Computational Dynamics, Co., London. U. K, 2004
[16] K.W. McAlister and R.K. Takahashi, "NACA0015 Wing Pressure and Trailing Vortex Measurements," NASA Technical Paper 3151, November 1991.
[17] K. Dejong, "An Analysis of the Behavior of a Class of Genetic Adaptive Systems," Doctoral Thesis, Department of Computer and Communication Sciences, University of Michigan, Ann Arbor, 1975
[18] J.D. Anderson, Jr, Aircraft Performance and Design, McGraw-Hill, 1999, Chap 2.