• 제목/요약/키워드: flame propagation velocity

검색결과 142건 처리시간 0.021초

CNG 기관의 수소혼합률 변화에 따른 성능 및 배출가스 특성에 관한 실험적 연구 (An Experimental Study on Performance and Emission Characteristics of Hydrogen Mixtures in a CNG Engine)

  • 김인구;손지환;김정화;김선문;김정수;이성욱
    • 한국수소및신에너지학회논문집
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    • 제27권4호
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    • pp.357-364
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    • 2016
  • Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the combustion stability and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

반응성 유기물 분진의 폭발특성과 열안정성 (Explosion Properties and Thermal Stability of Reactive Organic Dust)

  • 한우섭;한인수;최이락;이근원
    • 한국가스학회지
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    • 제15권4호
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    • pp.7-14
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    • 2011
  • 20 L 구형 폭발시험장치와 시차주사열량계(DSC)를 사용하여 반응성 유기물 분진의 폭발 및 열분해 특성을 실험적으로 조사하였다. 그 결과 97 % Benzoyl peroxide(BPO), Phthalic anhydride(PA), 1-Hydroxybenzotri azol(HBT)의 폭발하한은 매우 낮은 농도인 10~15 g/$m^3$의 범위로 측정되어 착화위험성이 높은 것으로 나타났다. HBT, PA 및 97 % BPO의 폭발지수는 각각 251, 146, 80 [bar m/s]로서, HBT는 폭발등급 2에 해당한다. 또한 밀폐계 분진폭발의 화염전파 특성을 추정하기 위하여 용기면에의 화염도달시간과 폭발압력을 고려하여 화염전파속도를 예측하였다. 97 % BPO 및 HBT의 열분해 개시온도와 발열량은 각각 $107^{\circ}C$(1025 J/g), $214^{\circ}C$(1666 J/g)로 나타났는데, 이와같이 낮은 열분해 온도와 큰 발열량이 폭발특성에 영향을 주는 것으로 판단된다.