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International Journal of Automotive Technology

, Volume 13, Issue 6, pp 905–914 | Cite as

Aerodynamic design optimization of rear body shapes of a sedan for drag reduction

  • K. S. Song
  • S. O. Kang
  • S. O. Jun
  • H. I. Park
  • J. D. Kee
  • K. H. Kim
  • D. H. Lee
Article

Abstract

This study proposes an aerodynamically optimized outer shape of a sedan by using an Artificial Neural Network (ANN), which focused on modifying the rear body shapes of the sedan. To determine the optimization variables, the unsteady flow field around the sedan driving at very fast speeds was analyzed by CFD simulation, and fluctuations of the drag coefficient (C D ) and pressure around the car were calculated. After consideration of the baseline result of CFD, 6 local parts from the end of the sedan were chosen as the design variables for optimization. Moreover, an ANN approximation model was established with 64 experimental points generated by the D-optimal methodology. As a result, an aerodynamically optimized shape for the rear end of the sedan in which the aerodynamic performance is improved by about 5.64% when compared to the baseline vehicle is proposed. Finally, it is expected that within the accepted range of shape modifications for a rear body, the aerodynamic performance of a sedan can be enhanced so that the fuel efficiency of the sedan can be improved. The YF SONATA, a sedan manufactured by Hyundai Motors Corporate, played a major role in this research as the baseline vehicle.

Key Words

Design optimization Automotive aerodynamics Drag reduction Rear end shape YF SONATA 

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Copyright information

© The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • K. S. Song
    • 1
  • S. O. Kang
    • 1
  • S. O. Jun
    • 1
    • 3
  • H. I. Park
    • 1
  • J. D. Kee
    • 1
    • 2
  • K. H. Kim
    • 1
    • 3
  • D. H. Lee
    • 1
    • 3
  1. 1.School of Mechanical and Aerospace EngineeringSeoul National UniversitySeoulKorea
  2. 2.Central Advanced Research and EngineeringInstitute of Hyundai-Kia Motors Corporate, R&D DivisionGyeonggiKorea
  3. 3.School of Mechanical and Aerospace Engineering, Institute of Advanced Aerospace TechnologySeoul National UniversitySeoulKorea

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