Fire Science and Engineering (한국화재소방학회논문지)

Korean Institute of Fire Science and Engineering (한국화재소방학회)
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Experimental Study on the Flame Spread Characteristics under Reduced Atmospheric Pressures and Elevated Oxygen Concentrations

저기압 고산소 환경에서 화염 전파특성에 관한 실험적 연구

  • Yang, Ho-Dong (Department of Automobiles, Chosun College of Science & Technology) ;
  • Kwon, Hang-June (Department of School of Mechanical System Engineering, Graduate School of Chosun University) ;
  • Park, Seul-Hyun (School of Mechanical System & Automotive Engineering, Chosun University)
  • 양호동 (조선이공대학교 자동차과) ;
  • 권행준 (조선대학교 대학원) ;
  • 박설현 (조선대학교 기계시스템.미래자동차공학부)
  • Received : 2016.10.31
  • Accepted : 2016.12.15
  • Published : 2016.12.31
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Abstract

The characteristics of flame spread under similar atmospheric conditions to those inside the first stage of launch vehicles were investigated to provide fundamental knowledge to prevent fires and explosions of vehicles during launching operations. To this end, the rate of flame spread on the solid fuel was measured at elevated oxygen concentrations and reduced atmospheric pressures. A 0.18 mm diameter optical fiber was used as a solid fuel. The experimental results indicated that elevated oxygen concentrations can increase the rate of flame spread while increasing the atmospheric pressures to 1 atm can lead to decreases in the rate of flame spread. The increases in the rate of flame spread with pressure is due mainly to reductions in the convective heat loss that are clarified through an analysis of the pressure dependence on the convective heat transfer coefficient.

발사체의 지상 운영과정이나 발사과정에서 일어날 수 있는 화재와 폭발사고 예방을 위해 1단 동체 내부에 형성될 수 있는 연소 환경에서 화염의 전파특성을 고찰해 보았다. 이를 위해 1단 동체 내부에 형성될 수 있는 고산소-저기압 환경을 연소챔버 내에 조성하고 고체연료를 점화시켜 화염 전파율을 측정하였다. 고체연료로는 두께가 0.18 mm인 광섬유를 사용하였다. 주어진 조건에서 산소농도가 증가함에 따라 광섬유를 따라 전파하는 화염의 속도는 급격히 증가하였지만 챔버 내의 압력이 대기압에 가까질 수록 화염의 전파속도는 감소하였다. 압력 증가에 따른 화염전파율의 감소의 원인을 파악하기 위해 대류열전달계수와 화염전파율의 압력 상관성 분석해 보았으며, 이를 통해 압력이 낮아질수록 대류 열손실이 줄어들어 화염전파율이 증가하는 것을 확인하였다.

Keywords

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