• 제목/요약/키워드: Combustion properties

검색결과 821건 처리시간 0.022초

SHS 마이크로파에 의한 (Ti.Si)C 복합체의 합성 및 소결특성에 관한 연구 (Study on Synthesis and Characterization of (Ti.Si)C Composite by SHS Microwave)

  • 이형복;권상호;이재원;안주삼
    • 한국세라믹학회지
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    • 제32권9호
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    • pp.1009-1018
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    • 1995
  • (Ti.Si)C composite powders were synthesized by SHS method using microwave energy. Compositional and structural characterization of the powder were carried out by using scanning electron microscopy and X-ray diffraction. The average particle size of the synthesized (Ti.Si)C composite powders was smaller than that of the starting materials. From the results of the temperature profile, combustion temperature and velocity were decreased with increasing Si molar ratio. With increasing C molar ratio combustion temperature and velocity did not change. (Ti.Si)C composite was sintered at 185$0^{\circ}C$ for 60 min by using hot-pressing with 30 MPa. The best properties were obtained from the sintered specimen whose composition was 1 : 1 : 1.9 molar ratio of Ti : Si : C. The sintering density, flexural strength and vickers hardness of the sintered body were 4.71 g/㎤, 423 MPa and 21 GPa, respectively.

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CONE CALORIMETER STUDIES OF WOOD SPECIES

  • Grexa, Ondrej;Horvathova, Elena;Osvald, Anton
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.77-84
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    • 1997
  • Cone calorimeter measurements can be used for the calculation of effective material properties, which can be used as input parameters in modeling of fire. Main parameter measured in Cone calorimeter is heat release rate. Some other parameters as time to ignition, effective heat of combustion, mass loss rate or total heat released is also measured in Cone calorimeter. Total heat released is important from the point of view of total energy available in material in Fire situation. Cone calorimeter. measurements were done on several wood species (oak, beech, spruce, poplar). Measurements were provided at external irradiances 30, 50 and 65 ㎾/$m_2$ in horizontal orientation. Heat release rate data were evaluated and compared as a function of external irradiance for various species of wood. furthermore the influence of external irradiance on effective heat of combustion and total heat release was also evaluated for the period of flame combustion.

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연소열을 이용한 유기할로겐화탄화수소류의 폭발한계의 예측 (Prediction of Explosion Limits of Organic Halogenated Hydrocarbons by Using Heat of Combustions)

  • 하동명
    • 한국화재소방학회논문지
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    • 제26권4호
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    • pp.63-69
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    • 2012
  • 폭발한계는 가연성물질의 폭발위험성을 결정하는데 중요한 특성치 가운데 하나이다. 본 연구에서는 연소열과 화학양론계수를 이용하여 유기할로겐화탄화수소의 폭발하한계와 상한계를 예측하였다. 제시된 예측식에 의한 폭발한계 값은 문헌값과 적은 오차범위에서 일치하였다. 제시된 방법론을 사용하여 다른 가연성 유기할로겐화탄화수소류의 폭발한계 예측이 가능할 것으로 판단된다.