Journal of the Korean Society of Visualization (한국가시화정보학회지)

The Korean Society of Visualization (한국가시화정보학회)
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Experimental study on the drag reduction of a helmet for paragliding

패러글라이딩 헬멧의 항력 감소에 관한 실험적 연구

  • Hwang, Jongbin (Department of Mechanical Engineering, Ulsan National Institute of Science and Technology) ;
  • Park, Jungmok (Gin Gliders Inc.) ;
  • Song, Jinseok (Gin Gliders Inc.) ;
  • Kim, Jooha (Department of Mechanical Engineering, Ulsan National Institute of Science and Technology)
  • Received : 2021.09.27
  • Accepted : 2021.11.04
  • Published : 2021.12.31
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Abstract

In the present study, wind tunnel experiments were performed to reduce the drag of a paragliding helmet in the range of Reynolds numbers from 46,000 to 155,000. The drag force of the helmet model with dimples and deflectors installed was measured by varying the dimple depth and the slant angle of the deflector. The dimples were effective in reducing the drag at low Reynolds numbers, but no significant drag reduction was found in the Reynolds number range in which an actual paraglider flight takes place. On the other hand, the deflector installed tangentially to the side outline of the helmet showed an average drag reduction of 7% in the flight Reynolds number range of real paragliding. This was because the deflector shrunk the size of the wake region and moved the wake region downstream of the deflector.

Keywords

Acknowledgement

본 연구는 문화체육관광부의 스포츠 선도기업 핵심기술개발사업(S202101-05-01-02)을 통해 국민체육진흥공단의 국민체육진흥기금을 지원받아 수행되었으며, 이에 감사드립니다.

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