• Title/Summary/Keyword: flash-over

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Study on building room fire development stages (건축물 실내화재의 단계에 대한 연구)

  • Cha, Jong-Ho
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.169-172
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    • 2008
  • The purpose of this paper is to summarize characteristics of fire growth stages, combustion proceeding, human behavior factors against fire, fire active protections, fire alarms in order to perform public safety and protection, personnel property protection, with identification of economic analysis aspects based on respective stages classified as fire generation- fire growth- flashover- fire extinction, which is differ from previous studies that based on distinct concepts such as fire stages, escapes, building construction, fire sensing.

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A Full-scale Fire Test of an Apartment House (공동주택 실물화재 실험)

  • Kim, Myung-Bae;Han, Yong-Shik;Choi, Byung-Il;Do, Kyu-Hyung;Lee, Yu-Whan
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2009.04a
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    • pp.415-422
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    • 2009
  • 국내 저층 공동주택 화재시의 화재 전파 경로와 상층으로의 화재 전파를 살펴보기 위하여 4층 공동 주택을 대상으로 실물화재 실험을 수행하였다. 화재는 3층 주택에서 발화하는 것으로 하였고, 초기 화원은 주방에서 과열된 식용유에 발화되어 발생하는 것으로 하였다. 주택 내부 가연물은 일반 가정의 필수 가연물을 모두 포함 하였다. 내부 화재 성상을 확인하기 위하여 가시화, 주요부의 온도측정, 산소농도 측정을 수행하였다. 실험 결과 초기 화원의 발화 시간, 화재 층 내부 각 구획으로의 전파시간, 전역화재 발생시간을 파악하였으며, 상층으로의 연소확대 경로를 파악하였다.

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A Study on the Limit Heat Release Rate for the Prediction on Fire Characteristics in the Compartment Space (구획공간의 화재성상 예측을 위한 한계 열방출률에 관한 문헌고찰)

  • Huh, Ye-Rim;Lee, Byeong-Heun;Kwon, Young-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.11a
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    • pp.111-112
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    • 2020
  • In the case of, the ignition of flammable external materials by the radiant flame and the accompanying fire in the upper layer are occurring every year, and in the case of the Flashover prediction formula, the limit is reached through the surface area of the space and the factor. Predicts heat release rate. In this study, the critical heat release rate of each prediction formula was calculated based on the ISO 9705 model.

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The Characteristics of Arc Scattering and Fusing Current of Copper Wire in the Fault Process DB System of Cables in a PL Environment

  • Kim, Young-Seok;Shong, Kil-Mok;Kim, Sun-Gu
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.3
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    • pp.52-58
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    • 2008
  • The importance of. identifying the causes of electrical faults cannot be overstated because of the accidents caused by over-current that take place at the home, the office and electrical facilities due to misuse, poor products and system faults. It is necessary to gather objective, scientific data pertaining to electrical fault investigation in a product liability(PL) environment. To date, no database(DB) has been built concerning the accurate cause analysis of faultyfacilities. In this paper, accident hazard and arc scattering when over-current flows in copper wire was investigated. It was found that when over-current flows in a copper wire, the copper wire became heated and bent and beads were scattered around the wire with a flash. It was determinedthat the fusing current and time was related to the current rise per second. For example, when the current rise per second was largethe fusing current was higher than when the current rise per second was small, and the beads dispersed along a wide area. Fusing time, however, was shorter. The possibility of electrical fault became highest when the fusing current was higher. As the current rise per second is short, the dendrite structure is distributed in the surface of the copper wire. These experimental results can be utilized for a fault process DB system in the investigation and the prevention of electrical faults.

A Study on Flash Over Delay Effects on Applied Plate-Fire Spread Prevention Method at Sandwich Panels Structure (샌드위치패널 건축물 플래시오버 지연을 위한 화재확산방지플레이트 시공방법 연구)

  • Kim, Do-hyun;Cho, Nam-Wook
    • Fire Science and Engineering
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    • v.31 no.3
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    • pp.79-87
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    • 2017
  • Sandwich panels which are having the both sides are bonded with a heat insulating material with an iron plate are used as factories, warehouse structures as advantages of convenience in construction at economic efficiency of material cost. However, in a panel structure constructed by continuous joining of sandwich panels, a joint portion where a panel and a panel are connected is generated. The joint part is a part which is easily vulnerable to fire because flames easily flow into the melting and deformation of the iron plate during fire. The flames flowing into the panel induce diffusion of fire by rapid burning, causing damage of human life and property. In this research, we developed a flame spread prevention plate to prevent spreading of sandwich panel. This is an improvement of the workability by the anti-spreading construction method of the existing previous research, it can be applied independently to the connecting part where the panel and the panel are coupled, designed to prevent inflow and spreading of flame did. The actual fire test of the test method of KS F ISO 13784-1 of the sandwich panel specimen was conducted and the burning behavior corresponding to the presence or absence of application of the flame spread prevention plate was grasped at the panel connection part and its effect was measured. Inserting a fire spreading plate into the test result panel connecting part is measured by delaying the flashover, prevention of collapse of the specimen, and temperature rise of the opening, effectively improving the fire safety of the panel structure It was confirmed as a method that can be secured. It is judged that panel structure will contribute to ensuring fire safety by applying the fire spread prevention construction method of various methods ensuring the workability and economy of panel connection vulnerable to fire.

Simulation on the Heating Performance of a 2-Stage Compression Heat Pump System Using River Water (하천수열원을 이용한 2단압축 열펌프의 난방성능 시뮬레이션)

  • Park Chasik;Kim Bohyun;Kim Yongchan;Lee Young Soo;Bang Ki-young
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.11
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    • pp.1005-1013
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    • 2005
  • The use of river water as a heat source of a heat pump has the advantage in the performance compared to the use of atmospheric air because the temperature variation of river water over the year is relatively small. In this study, the performance of the heat pump system using river water as a heat source was numerically investigated. A simulation model for the 2-stage compression heat pump system was developed with each component model composed of compressors, heat exchangers, a flash tank and electronic expansion devices. The peformance of the heat pump system using river water was improved by $50\%$ compared to that using atmospheric air in winter conditions.

An Economic Analysis of Desalination for Potential Application in Korea (국내 적용을 위한 해수 담수화 경제성 분석)

  • Park, No Suk;Park, Hee Kyung;Park, Mi Hyun;Kim, Byung Duck
    • Journal of Korean Society of Water and Wastewater
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    • v.12 no.3
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    • pp.48-54
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    • 1998
  • Korea becomes one of the countries which suffer from water shortage. It is expected that its water shortage in the early 2000's will be more than 10% of the annual demand. The shortage problem is more serious in the coastal areas where many industry complex locate. To solve the shortage problem, seawater desalination gets more attention as an alternative water supply source since Korea is surrounded by sea on its three sides. For potential application of seawater desalination in Korea, an economic analysis was conducted using cost data for the plants in the Middle Ease areas, The United states and others. The study is to provide a basis for the government to establish a strategy for promoting seawater desalination in Korea. It is discussed that the Reverse Osmosis (RO) process gets cheaper over times than the thermal processes of Multi-stage Flash Distillation (MSF) and Multi Effect Distillation (ME), especially in case where the capacity is less than about 50,000 ton/day. The unit cost of RO seawater is analyzed about US$1.35/ton in 1990 price. Since the Desalination plant can be operated regardless of weather conditions, industries in Korea's coastal areas which suffer from frequent droughts and water shortages are recommended to look into this option with more attention.

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A Study on the Change of Physical Properties of Engine Oil after Vehicle Driving (차량 운행에 따른 엔진오일 물성변화 연구)

  • Lim, Young-Kwan;Ham, Song-Yi;Lee, Joung-Min;Jeong, Choong-Sub
    • Tribology and Lubricants
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    • v.28 no.2
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    • pp.93-98
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    • 2012
  • The engine oil is an oil used for lubrication of various internal combustion engines. Recently, the vehicle and engine oil manufacture usually guarantee for oil change over 15000~20000 km mileage, but the most of driver usually change engine oil every 5000 km driving in Korea. In this case, it is possible to cause environmental contamination by used engine oil and increase the cost of driving by frequently oil change. In this study, we investigate the various physical properties such as flash point, pour point, kinematic viscosity, cold cranking simulator, total acid number, and four-ball test for fresh engine oil and used engine oil after vehicle driving (5000 km, 10000 km). The test result showed that the total acid number and wear scar by four-ball test of used engine oil had increased than fresh engine oil, but 2 kind of used oil (5000 km and 10000 km) had similar physical properties.

A Numerical Analysis for Fire Spread Mechanism of Residential Building Fire (주거용 건축물의 화염전파 현상에 대한 수치해석적 검토)

  • Ahn, Chan-Sol;Kim, Heung-Youl;You, Yong-Ho;Kim, Hyung-Jun
    • Fire Science and Engineering
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    • v.26 no.1
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    • pp.31-37
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    • 2012
  • This study is intended to present a computational thermal model for a residential building. As the Performance Based Design is more popular, fire-intensity and fire-load have turned out to be very important factors for building design and can be predicted through some computational work. To predict and estimate the fire properties of a residential fire, we made some numerical models of combustibles and residential building. In a bid to validate the estimate values, computational analysis results from numerical models were compared with real fire tests. For computational analysis, the Fire Dynamics Simulator (FDS) was used with Large Eddy Simulation (LES) model for turbulence. Consequently, fire-intensity was well predicted and flash-over of rooms were successfully estimated.

Case Reports and Studies on the Functional Process of Panic Disorder, treated with Ling-Gui-Gan-Zao-Tang (령계감조탕 투여로 치료된 공황장애 환자 사례 분석 및 처방의 작용 기전 고찰)

  • Roh, Young-Beum;Yun, Su-min;Joh, Eun-suk
    • 대한상한금궤의학회지
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    • v.4 no.1
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    • pp.1-12
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    • 2012
  • Objective : The purpose of this study is to find out the effectiveness of Ling-Gui-Gan-Zao-Tang for patients of panic disorder. Method : To achieve the purpose of this study, Ling-Gui-Gan-Zao-Tang was prescribed for three months to two different patients of panic disorder. They were diagnosed as panic disorder in department of neuropsychiatry, and had no other prescribed decoction or psychotherapy. Results : 1. The BAI score for anxiety were decreased in both patients, and they got improved overall symptoms. 2. In panic attack, patients are in dominant state of sympathetic nerve, so they have palpitaion and get nervous. Fu-Ling(茯笭) can treate this kind of situation. 3. Based on and , urgent situation, over-tension of muscles, hot flash can be treated Gancao(甘草), Dazao(大棗), Guizhi(桂枝) respectively. Conclusions : When panic disorder attaks, the sympathetic nerves are dominant in patient's body. So they feel palpitating, sweating, suffocating. Ling-Gui-Gan-Zao-Tang can treat this series of symptoms.