• Title/Summary/Keyword: 열방출량

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Combustion Properties of Woods for Indoor Use (I) (실내사용 목재의 연소 특성 분석(I))

  • Son, Dong Won;Kang, Seog-Goo
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.6
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    • pp.675-681
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    • 2014
  • The purpose of this study is to analyze fundamental combustion characteristics of woods used for indoor applications. The combustion characteristics such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter or thermogravimetry. These analysis results show that material properties of wood are closely related to flammability. It was shown that the relationship between the mass loss and gas emission. The results of combustion properties of woods would be useful for fundamentals of guiding the safe use of wood indoor application.

Effect of Fire Danger Reduction by Cover rate of a Herbaceous Plant (초본류 피복율에 따른 산불위험 저감 효과)

  • Kim, Dong-Hyun
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.04a
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    • pp.412-415
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    • 2011
  • 본 연구에서는 개엽된 지표 식물이 건조된 낙엽층에 비해 수분함유량이 상대적으로 많은 것에 착안하여 피복율이 증가하고 개엽량이 많아짐에 따라 산불위험성이 낮아진다는 가정을 세워 열방출량 실험분석과 함께 화염높이 등을 비교, 평가하였다. 그 결과, 초본류의 피복율 및 개엽량이 증가할수록 열방출량이 비례적으로 감소하는 경향을 나타내었고 화염높이 또한 현저히 감소되는 결과를 나타내었다. 향후, 본 연구 결과를 바탕으로 봄철 순기별, 지역별 산림 식물의 개엽량을 모니터링하여 산불위험도 및 산불확산예측에 반영해야 될 것으로 판단된다.

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Thermal Characteristics of Living Leaves in Pinus Densiflora with Heat Flux (복사열 증가에 따른 소나무 생엽의 열적특성 분석)

  • Park, Young-Ju;Lee, Hae-Pyeong
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.5
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    • pp.75-82
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    • 2010
  • To study the combustion characteristics of forest fuel by fire intensity, the experiment of combustion characteristics on Pinus Densiflora living leaves, which is the weakest species to the forest fire, was delivered, using variables of heat flux(25 kW/$m^2$, 50 kW/$m^2$, 75 kW/$m^2$). With the equipment of Cone calorimeter, the characteristics of ignition, heat, smoke release, CO and $CO_2$ release, and mass loss were analyzed. Pinus Densiflora living leaves containing moisture of 60.66% were not ignited at the heat flux of variables 25 kW/$m^2$, 50 kW/$m^2$, 75 kW/$m^2$. In proportion to the heat flux value, heat release amount and heat release rate reached maximum value rapidly: higher variables came to the maximum by the half rapidity and the maximum value were twice higher than the former lower variables respectively. As for the smoke release, the less heat flux the variable had, the more smoke release it had, due to incomplete combustion. The release amount of CO and $CO_2$ had more maximum value as the heat flux increased and more radiant heat meaned more carbon oxide. When the forest fire breaks out, therefore, a great amount of CO and $CO_2$ will be released by Pinus Densiflora.

산림 내 주요 시설물 주변 낙엽 및 광솔의 연소특성 실험

  • Yeom, Chan-Ho;Lee, Si-Yeong;Gwon, Chun-Geun
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2013.04a
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    • pp.178-178
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    • 2013
  • 본 연구는 산림 내 주요 시설물 주변의 소나무, 리기다소나무, 해송, 잣나무, 굴참나무낙엽 5종 및 소나무광솔 등 주요 산불연료에 대하여 연소특성을 분석하고자 착화특성과 전파특성을 실험 한 결과, 발화온도의 경우 소나무낙엽($285^{\circ}C$)이 가장 낮게 측정되어 발화위험성이 가장 높은 것으로 나타났으며, 착화시간의 경우 굴참나무낙엽(발화온도 $305^{\circ}C$)이 3초로 가장 빠르게 나타났고, 화염유지시간의 경우 굴참나무낙엽이 가장 긴 것으로 나타났다. 또한, 전파특성 실험결과 소나무 광솔이 총열방출량 $72MJ/m_2$, 평균열방출율 $40KW/m_2$, 최대열방출량 $206KW/m_2$로 가장 높았으며, 두번째는 소나무낙엽으로 나타났다. 따라서, 실제 산불에서도 소나무광솔과 소나무낙엽이 화염전파에 더 영향을 줄 것으로 사료되었고, 또한, 연료별 탄소배출량 분석 결과 평균$CO_2$방출량이 가장 큰 수종은 리기다소나무낙엽(1.33kg/kg)이며, 평균CO방출량이 가장 큰 수종은 굴참나무 낙엽(0.075kg/kg)으로 나타났다.

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Temporal and spatial distributions of heat fluxes in the East Sea(Sea of Japan) (東海熱收支 의 時.空間的인 分布)

  • 박원선;오임상
    • 한국해양학회지
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    • v.30 no.2
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    • pp.91-115
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    • 1995
  • Air-sea heat fluxes in the East Sea were estimated from the various ship's data observed from 1961 to 1990 and the JMA buoy #6 data from 1976 to 1985. The oceanic heat transport in the sea was also determined from the fluxes above and the heat storage rate of the upper layer of 200m from the sea surface. In winter, The incoming solar radiation is almost balanced with the outgoing longwave radiation. but the sea loses her heat through the sea surface mainly due to the latent and sensible heat fluxes. The spatial variation of the net surface heat flux is about 100 Wm/SUP -2/, and the maximum loss of heat is occurred near the Tsugaru Strait. There are also lots of heat losses in the southern part of the East Sea, Korea Strait and Ulleung Basin. Particularly, the heat strong loss in the south-western part of the sea might be concerned with the formation of her Intermediate Homogeneous Water. In summer, the sea is heated up to about 120∼140 Wm/SUP -2/ sue to strong incoming solar radiation and weak turbulent heat fluxes and her spatial variation is only about 20 Wm/SUP -2/. The oceanic heat flux is positive in the southeasten part f the sea and the magnitude of the flux is larger than that of the net surface heat flux. This shows the importance of the area. In the southwestern part of the sea, however, the oceanic heat flux is negative. This fact implies cold water inflow, the North Korean Cold Water. The sigh of net surface heat flux is changed from negative to positive in March and from positive to negative in September. The heat content in the upper surface 200 m from the sea surface reaches its minimum in March and maximum in October. The annual variation of the net surface heat flux is 580 Wm/SUP -2/ in southwestern part of the sea. The annual mean values of net surface heat fluxes are negative, which mean the net heat transfer from the sea to the atmosphere. The magnitude of the flux is about 130 Wm/SUP -2/ near the Tsugaru Strait. The net surface fluxes in the Korea Strait and the Ulleung Basin are relatively larger than those of the rest areas. The spatial mean values of surface heat fluxes from 35$^{\circ}C$ to 39$^{\circ}$N are 129, -90, -58, and -32 Wm/SUP -2/ for the incoming solar radiation, latent hear flux, outgoing longwave radiation, and sensible heat flux, respectively.

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Experiments on the Behavior of Underground Utility Cable in Fire (지하구 케이블의 연소특성 실험)

  • 박승민;김운형;윤명오
    • Fire Science and Engineering
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    • v.16 no.2
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    • pp.75-80
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    • 2002
  • In this paper, some experiments of a heat release rate and toxicity for underground utility 22.9kv cable in fire was conducted and analysed applying plume equation and smoke chamber test separately, A 22.9 ㎸ power cable is selected for testing heat release in ISO 9705 geometry and toxicity production is measured with NES 713 (British-Naval Engineering Standard)test. In test results, Cable heat release reached about 60 ㎾ above 1.2 m from heptane pan and CO generated lethal concentration under 30 min. exposure condition.

The Study on Fire Characteristics of Furniture (가구류에 대한 화재 특성 연구)

  • Kweon, Oh-Sang;Yoo, Yong-Ho;Kim, Heung-Youl;Lim, Young-Soo
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2009.04a
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    • pp.379-384
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    • 2009
  • 본 연구에서는 다세대 주택에서 발생되는 화재에서 가연물질이 되는 가구류에 대한 화재 특성을 파악하기 위해 단위 가연물에 대한 열방출율(HRR, Heat Release Rate), 연기발생량, 유독가스 발생량 등에 대한 기본 DB를 확보하고자 하였다. 실험에 사용된 단위가연 물에는 침대(매트리스 포함), 장롱, 화장대, 책상, 책장, 소파(3+1인용), TV, 싱크대(찬장포함), 냉장고, 이불(옷가지)등 총 12여종이며, 국제 시험 규격인 ISO 9705 시험법인 중규모 시험 장치(Room Corner Tester)와 10MW 급의 실규모화재실험장치(Large Scale Calorimeter)에서 실험을 진행하였다. 실험결과 냉장고에서 가장 높은 최대 열방출율 약 3051 kW, 장롱에서의 일산화탄소 방출량은 최대 약 3894.2 ppm, 이산화탄소의 방출량은 최대 약 1.8% 로 가장 높게 측정되었다. 이러한 중규모 시험 장치를 통한 단위 품목의 화재특성 DB 작성은 단위구획에서의 화재 확산 예측에 가장 중요한 요소가 될 수 있을 것이다.

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Combustion Characteristics and Thermal Properties for Wood Flour-High Density Polyethylene Composites (목분-고밀도폴리에틸렌 복합체의 연소성 및 열적특성)

  • Shin, Baeg-Woo;Chung, Kook-Sam
    • Fire Science and Engineering
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    • v.26 no.1
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    • pp.89-95
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    • 2012
  • In this study, we were manufactured wood flour-HDPE composites by modular co-rotating twin screw extruder with L/D ratio of 42. We was measured cone calorimeter test and thermogravimetric analysis (TGA) to find the combustion characteristics and thermal properties for wood flour-HDPE composites. We then evaluated the effect of three additive-type flame retardants on fire resistance performance. The cone calorimeter test showed that the heat release rate (HRR) of untreated composites was the highest Peak HRR ($446.6kW/m^2$) as well as Mean HRR ($185.5kW/m^2$). From the TGA, it was shown that composites added flame retardants began early thermal decomposition and improved thermal stability.

A Numerical Simulation of the Atmospheric Fields Related to Anthropogenic Heat Flux and Surface Characteristics (인공열과 지표 특성에 따른 기상장 수치모의)

  • 이화운;김유근;원경미;김미향
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.220-221
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    • 2000
  • 도시화가 진행될수록 인구 집중과 고층 건물의 점유 증가를 초래하고 이로 인해 도심내 공장의 증가, 자동차의 폐열량 증가, 겨울철 연료와 여름철 냉방에 의한 에너지 사용량이 증가된다. 이때 방출된 열원으로 인해 인공열 배출량이 커지게 된다. 단위면적에 대해 방출되는 열플럭스가 도시마다 큰 차이를 보이는데(Landsberg, 1981) 시드니 외곽부에 비해 도심내의 연간 에너지 사용량이 360배에 달한다는 것을 보였다. (중략)

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