Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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A Numerical Investigation on the Wake Flow Characteristics and Rear-Spoiler Effect of a Large-Sized Bus Body

대형버스 바디모델의 후류특성 및 후미 스포일러 효과에 관한 해석적 고찰

  • 김민호 (기아자동차 상용연구소) ;
  • 국종영 (기아자동차 상용연구소) ;
  • 천인범 (기아자동차 상용연구소)
  • Published : 2003.03.01
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Abstract

The aerodynamic characteristics of automobiles have received substantial interest recently. Detailed knowledge of the vehicle aerodynamics is essential to improve fuel efficiency and enhance stability at high-speed cruising. In this study, a numerical simulation has been carried out for three-dimensional turbulent flows around a commercial bus body. Also, the effect of rear-spoiler attached at rear end of bus body was investigated. The Wavier-Stokes equation is solved with SIMPLE method in general curvilinear coordinates system. RNG $k-\varepsilon$ turbulence model with the MARS scheme was used for the evaluating aerodynamic forces, velocity and pressure distribution. The results showed details of the three-dimensional wake flow in the immediate rear of bus body and the effect of rear-spoiler on the wake structure. A maximum of 14% reduction in drag coefficient was achieved for a model with a rear-spoiler.

Keywords

References

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