Experimental Study on Downwardly Spreading Flame over Inclined Polyethylene-insulated Electrical Wire with Applied AC Electric Fields

교류전기장이 인가된 폴리에틸렌으로 피복된 기울어진 전선을 통해 하향으로 전파하는 화염에 대한 실험적 연구

  • Lim, Seung Jae (Interdisciplinary Program of Biomedical Engineering, Pukyong National University) ;
  • Park, Jeong (Department of Mechanical Engineering, Pukyong National University) ;
  • Kim, Min Kuk (Environmental & Energy System Research Division, Korea Institute of Machinery and Materials) ;
  • Chung, Suk Ho (King Abdullah University of Science and Technology, Clean Combustion Research Center) ;
  • Osamu, Fujita (Hokkaido University, Division of Mechanical and Science Engineering)
  • 임승재 (부경대학교 의생명융합공학협동과정) ;
  • 박정 (부경대학교 기계공학과) ;
  • 김민국 (한국기계연구원 환경에너지기계연구본부) ;
  • 정석호 ;
  • Received : 2014.09.25
  • Accepted : 2014.12.02
  • Published : 2014.12.30


An experimental study on downwardly spreading flame over slanted electrical wire, which is insulated by Polyethylene (PE), was conducted with applied AC electric fields. The result showed that the flame spread rate decreased initially with increase in inclination angle of wire and then became nearly constant. The flame shape was modified significantly with applied AC electric field due to the effect of ionic wind. Such a variation in flame spread rate could be explained by a thermal balance mechanism, depending on flame shape and slanted direction of flame. Extinction of the spreading flame was not related to angle of inclination, and was described well by a functional dependency upon the frequency and voltage at extinction.



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