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CFD PREDICTION OF AERODYNAMIC DRAG ACTING ON ALPINE DOWNHILL SKIER

알파인 스키 활강 선수에 작용하는 공기 저항 예측

  • Kim, J.S. (School of Naval Architecture and Ocean Engineering, Univ. of Ulsan) ;
  • Cho, T.S. (School of Exercise and Sports Science, Univ. of Ulsan) ;
  • Ahn, H.T. (School of Naval Architecture and Ocean Engineering, Univ. of Ulsan)
  • 김종수 (울산대학교 조선해양공학부) ;
  • 조태수 (울산대학교 스포츠과학부) ;
  • 안형택 (울산대학교 조선해양공학부)
  • Received : 2016.07.05
  • Accepted : 2016.09.27
  • Published : 2016.09.30

Abstract

In speed skiing, aerodynamic forces play an important role in determining performance of the skier. To predict aerodynamic effects of the posture of the skier on alpine downhill skiing, we constructed equation of motion of the skier and performed the corresponding CFD simulations. Comparing drag and lift of three different skier postures, it has been shown that drag decreases significantly by tucking upper body to lower body and stretching arms forward. Also, aerodynamic lift which worked as downforce in standing posture worked upward in tuck posture, reducing friction force between snow and ski. This indicates that tuck posture have advantages over standing posture in dual mechanism, namely by reducing drag and also increasing lift. By this two-dimensional initial study we could reveal the general tendency of the aerodynamic force over the skier's body. This study not only provides a theoretical foundation for the athletes to understand the aerodynamic effects of skier postures but also shed a light on towards more accurate and rational three-dimensional CFD simulation of skiers in the near future study.

Acknowledgement

Supported by : 한국연구재단

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