• 한국세라믹학회지
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• 제27권2호
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• pp.211-218
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• 1990

CA2-based clinker with highly activated surface and hydraulic properties was synthesized at a comparatively lowr temperature than that of conventional synthesis by "hydration-burning method". This consists of calcining the mixture of CaCO3 and Al2O3 to obtain a primary clinker, hydrating the primary clinker and reburning the hydrates to obtain final clinker. Burning of primary clinker above 1200℃ was necessary to eliminate free CaO in it and to obtain it's solid hydrate. However, rising the burning temperature above 1300℃ is ineffective due to the decrease in hydraulic properties of the primary clinker with the temperature. Hydration of primary clinker at the elevated temperature(>35℃) was required to obtain the hydrate with more porous structure and final clinker with more active surface. CA2 was formed and increased with temperature at above 1150℃, finally became a primary phase of the final clinker. However, burning at the temperature above 1300℃ resulted in reverse effect on the hydraulic properties of the final clinker due to rapid decrease in it's surface area with the temperature.

• Journal of the Korean Wood Science and Technology
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• 제31권1호
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• pp.41-45
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• 2003

MDF를 재료로 600, 800, 1,000, 1,200℃에서 소성 하여 우드세라믹을 제조한 후 소성 전 수지 함침율과 소성온도에 따른 우드세라믹의 표면온도를 조사하였다. 함침율, 소성온도 및 시간의 경과에 따라 표면온도가 증가하였으며, 1,200℃ 시료의 온도가 가장 높게 나타났다. 시간의 경과에 따른 표면온도의 하강은 800℃ 시료의 온도가 가장 빨리 감소하였다.

• 대한기계학회논문집
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• 제18권7호
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• pp.1833-1839
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• 1994

Experiments have been carried out to investigate the burning characteristics of waste tires in high temperature environments. The burning of waste tire chips consists of four stages ; evaporation of volatile matters, ignition, burning of volatile matters, and burning of solid carbon. Burning time of waste tire chips depends on the gas temperature and the initial weight of the chip. However, the environments. In the ceramic matrix burner with a ceramic radiation shield, the burning time of the waste tire chips becomes shorter than that without the shield. This is due to the increase in heat transfer to the tire chips by radiation.

• 임산에너지
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• 제22권1호
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• pp.24-29
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• 2003

낙엽송 간벌재 톱밥보드로 우드세라믹을 제조한 후 수지함침율 및 소성온도에 따른 우드세라믹의 표면온도 변화를 조사하였다. 히터의 표면온도가 증가함에 따라 우드세라믹의 표면온도도 급속히 증가하였으며 수지함침율 70∼80%, 소성온도 800∼1000℃ 조건으로 제조된 우드세라믹의 표면 온도가 상대적으로 높았다. 히터의 표면온도보다 우드세라믹 표면온도의 하강속도가 느려 우드세라믹이 오랜 시간 열을 유지하고 있음을 알 수 있었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제23회 KOSCO SYMPOSIUM 논문집
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• pp.104-110
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• 2001

Characteristics of lifted flame for highly diluted propane with nitrogen in high temperature coflowing air have been experimentally investigated, and the stabilization mechanism of lifted flame in high temperature air coflow have been proposed. As the coflow temperature increases, the liftoff height of flame decreased due to the increase of stoichiometry laminar burning velocity. At same coflow temperature, the difference of liftoff height between the fuel mole fractions has been disappeared by scaling the liftoff velocity with stoichiometry laminar burning velocity. It has been found that lifted flame can be stabilized for even smaller fuel velocity than stoichiometry laminar burning velocity. This can be attributed to buoyancy effect and the liftoff velocity characteristics for coflow temperature support it.

• 대한기계학회논문집B
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• 제27권9호
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• pp.1201-1208
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• 2003

The thickness of flame and preheat zone from burning velocity which was computed by using Premix code of Chemkin program for methane-air mixture. Also the thickness was evaluated from temperature profile which is also obtained from Premix code for the equivalence ratio of 0.5 to 1.6. The computations were carried out for the laminar flame thickness and burning velocity under the unburned gas temperature 0.5bat-30bar and temperature of 300K-700K at ${\Phi}=l.0$. Comparison of the results showed no difference between these two methods. The flame thickness was decreased by increasing the pressure and temperature, but, the affect of pressure is more significant than the effect of temperature on the flame thickness. The thickness of preheat zone was about 66.5% of the flame thickness, and flame thickness and burning velocity were also predicted by using empirical equation.

• 한국화재소방학회논문지
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• 제10권1호
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• pp.44-48
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• 1996

Burning rate of immobilized methyl and ethyl alcohols on ceramic balls was studied. Experiments were performed by burning methyl, ethyl alcohols immobilized on sands (particle size 0.35mm) and ceramic balls (particle size 1-5mm) to measure mass burning rate, height burning rate and combustion temperature. The longer time from ignition to extinguishment was resulted from the larger particle size of ceramic balls and the smaller size of ceramic balls exhibited the higher mass burning rate. Of alcohols tested the relative magnitude of facilitation of combustion was methyl ＞ ethyl. Combustion temperature of alcohols, without regard to the types of alcohols, was not increased with smaller ceramic balls(up to 3mm of particle size). However, with larger ceramic balls, combustion temperatare of alcohols was increased by 40-50$^{\circ}$ and the highest combustion temperatare was obtained with sands (particle size 0.35mm).

• 한국산업융합학회 논문집
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• 제12권3호
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• pp.137-142
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• 2009

Burning velocity of methane-air mixtures with water vapor have been measured to study the process of flame propagation using schlieren photographs and computation. The computations were carried out for the burning velocity using premix code of Chemkin program to compare the experimental results. The quantity of water vapor contained were changed 5% and 10% of total mixtures, and equivalence ratio of mixtures between 0.8 and 1.2 were tested under the ambient temperature 323K and 373K. The results showed little difference between these two methods, the burning velocity was decreased by increasing the water vapor contents due to the interruption of flame development. And, the effect of ambient temperature was less significant by increasing the water contents on the burning velocity.

• 한국추진공학회지
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• 제13권2호
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• pp.17-25
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• 2009

본 연구에서는 연소실의 축방향 압력과 속도변화를 고려한 비정상 내탄도 해석모델을 제안하고 이를 바탕으로 침식연소에 미치는 인자를 해석하였다. 개발 모델의 검증을 위하여 침식연소가 없는 경우와 침식연소가 있는 경우에 대하여 선행연구 결과와 비교하였으며 해석결과가 일치함을 확인하였다. 연소실 압력, 그레인 길이, 그레인 초기온도, 추진제 기화온도가 침식연소에 미치는 영향을 조사하였다.

• 한국화재소방학회논문지
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• 제29권6호
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• pp.119-128
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• 2015

이 논문에서는 신축 후 약 2년이 경과한 전원주택에서 벽난로 가동 중에 벽난로로 인한 화재가 발생하여 전소된 사례에 대해 법원을 통해 소방서, 경찰서, 화재보험관련 조사기관, 주택을 시공한 건설회사와 벽난로를 시공한 벽난로제조업체로부터 제공받은 자료들을 분석하여 벽난로 옆 벽체의 목재기둥에 남아 있는 저온장기발화의 화재패턴을 근거로 벽난로 옆 벽체의 목재기둥에 벽난로 화실(火室)의 열이 전도되어 화재가 발생하였음을 입증하였다. 그리고 벽난로 옆의 목재기둥이 저온장기발화를 한 이유는 굴뚝에 환기를 위한 공기창을 설치하지 않았기 때문임을 화재시뮬레이션을 통해 입증하였다.