• Title/Summary/Keyword: Fire spread rate

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A Study on Fire Spreading Prediction Program by Flow Field Analysis (유동장(流動場) 해석(解析)을 통한 산불확산예측(擴散豫測) 프로그램의 개발(開發))

  • Kim, Eng-Sik;Lee, Si-Young;Lim, Hoe-Jie;Kim, Hong;Song, Jong-Hun;Kim, Soo-Young
    • Journal of Korean Society of Forest Science
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    • v.87 no.4
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    • pp.528-534
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    • 1998
  • There are many parameters in prediction of forest fire spread. Among others wind and slope factors are considered to be the important parameters in spread of forest fire. Generally, all the inclined planes with same slopes can not have the same wind velocity in complex mountain area. But this effect has been disregarded in complex geometry. In this paper, wind values which have velocity and direction is calculated by applying computational fluid dynamics to the forest geometry. These results are applied for forest fire spreading algorithm with experimental Korean ROS(Rate Of Spread). Finally, the comparison between the simulation and the real forest fire has correspondence about 90%.

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Effects of Fire Curtain and Forced Smoke Ventilation on Smoke Spread to Auditorium in Stage Fire of Theater (공연장 무대 화재 시 방화막과 강제 배연구가 객석으로의 연기 확산에 미치는 영향)

  • Kim, Jae Han;Kim, Duncan;Lee, Chi Young
    • Fire Science and Engineering
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    • v.31 no.5
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    • pp.28-36
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    • 2017
  • In this work, the effects of fire curtain and forced smoke ventilation on smoke spread to auditorium in the stage fire of theater were investigated using the Fire Dynamics Simulator (FDS). For the stage of 31 m (Width)${\times}$34 m (Depth)${\times}$32 m (Height) in dimension, the fast growth fire condition with 10 MW of heat release rate was applied. The forced smoke ventilation was set based on the National Fire Safety Code (NFSC) and previous research. The gap distances between the fire curtain and proscenium wall was established to be 0 m and 0.5 m. When the fire curtain was attached completely to the proscenium wall without any gap, no smoke spread from the stage to the auditorium occurred, independent of forced smoke ventilation. When the gap distance between the fire curtain and proscenium wall was 0.5 m, the smoke layer in the stage descended to the lower height from the bottom than the case without the fire curtain, which was because the smoke spread to auditorium was impeded by the fire curtain. Under the same fire curtain condition, the case with the forced smoke ventilation led to decreasing the mass flow rate of outflow through the gap between the fire curtain and proscenium wall, as compared to the case without the forced smoke ventilation. Based on this study, it was confirmed that the fire curtain and forced smoke ventilation were the effective tools to hold down the smoke spread to the auditorium in the stage fire of theater.

A Numerical Study on the Effects of the Wind Velocity and Height of Grassland on the flame Spread Rate of Forest Fires (초지화재 발생시 바람의 속도 및 초본의 높이가 화염전파에 미치는 영향에 대한 수치해석적 연구)

  • Bae, Sung-Yong;Kim, Dong-Hyun;Ryou, Hong-Sun;Lee, Sung-Hyuk
    • Fire Science and Engineering
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    • v.22 no.3
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    • pp.252-257
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    • 2008
  • With the rapid exuberant growth of the forest, the number and size of forest fires and the costs of wildland fires have increased. The flame spread rate of forest fires is depending on the environmental variables like the wind velocity, moisture of grassland, etc. If we know the effects of the environmental variables on the fire growth, it is useful for wildland fiIre suppression. But analysis of the spread rate of wildland fire for these effects have not been established. In this study, the effects of wind velocity and height of grassland fuel have been investigated using the WFDS which is developed at NIST for prediction of the spread of wildland fires. The results showed that the relation between the height of the fuel and the spread rate of the head fires is, and the spread rates related to the wind velocity are predicted 17% less than the experimental results of Australia. When the wind velocity is over 7.5m/s, the concentration of pyrolyzed gas phase fuel is getting low due to fast movement of pyrolyzed gas, the flame spread rate becomes slow.

Research on FARSITE for introducing a Forest fire simulator (산불확산 시뮬레이션 도입을 위한 FARSITE 고찰)

  • Lee, Si-Young;Park, Houng-Sek
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.161-164
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    • 2008
  • We studied a basic concept and application about FARSITE, which is a forest fire spread simulator for preventing and predicting fire in United States Department of Agriculture(USDA). And, we researched a problem in the transition for introducing, so we serve the basic method for prevention and attacking fire. For this transition, we compared the behavior of the 2005 Yangyang forest fire with the result of a simulation. The spread direction is similar to real data. But, while mean spread of rate was 0.65km/hr on real data, it was 0.3km/hr on simulation. As Damaged area is 1,387ha on real, it was 5,368ha on simulation. Therefore, it is necessary to establish a fuel concept for more accurate simulation.

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A Room-Corner Fire Model을 적용한 건축내장재의 화재확산 특성 평가(1)

  • Kim, Un-Hyeong
    • Fire Protection Technology
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    • s.24
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    • pp.32-39
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    • 1998
  • A room-corner fire scenario of ISO 9705 with flame spread model developed by Quintiere is applied to the interior finish materials to show the sensitivity of properties derived from AST, E-1321 and ASTM E-1354 is investigated and various range of thermal properties by the author were analyzed in the model. There are including flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. The time for total energy release rate to reach 1MW is examined. Though some areas are neede for improvements, The model appears to predict good results with all the range of input properties and could be

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A STUDY on FOREST FIRE SPREADING ALGORITHM with CALCULATED WIND DISTRIBUTION

  • Song, J.H.;Kim, E.S.;Lim, H.J.;Kim, H.;Kim, H.S.;Lee, S.Y
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.305-310
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    • 1997
  • There are many parameters in prediction of forest fire spread. The variables such as fuel moisture, fuel loading, wind velocity, wind direction, relative humidity, slope, and solar aspect have important effects on fire. Particularly, wind and slope factors are considered to be the most important parameters in propagation of forest fire. Generally, slope effect cause different wind distribution in mountain area. However, this effect is disregarded in complex geometry. In this paper, wind is estimated by applying computational fluid dynamics to the forest geometry. Wind velocity data is obtained by using CFD code with Newtonian model and slope is calculated with geometrical data. These data are applied fer 2-dimentional forest fire spreading algorithm with Korean ROS(Rate Of Spread). Finally, the comparison between the simulation and the real forest fire is made. The algorithm spread of forest fire will help fire fighter to get the basic data far fire suppression and the prediction to behavior of forest fire.

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The Study on Surface Fire Spread in Fuel Bed (Fuel Bed에서의 지표화 확산에 관한 연구)

  • Kim, Jeong-Hun;Kim, Eung-Sik;Kim, Dong-Hyun;Kim, Jang-Whan
    • Fire Science and Engineering
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    • v.28 no.6
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    • pp.22-27
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    • 2014
  • In this study a Fuel bed where surface fire spreads through is made to measure the data such as the flame height, radiation, spread rate and temperature distribution of Fuel bed. As experimental variables species of trees, wind velocities and slop are chosen. Fallen leaves of Quercus Variabilis (Q.V.) and Pinus Densiflora (P.D.) are used as fuel. Wind velocity is controlled by simply designed wind turnnel from 1 to 5 m/s. Slope of fuel bed is changed from $0^{\circ}$ to $30^{\circ}$. For the measurements of temperature distribution and spread rate total 35 of K-type 1.6 mm thermocouples are positioned as a lattice design. Radiant heat flow meters are used besides video camera and thermovision camera.

An Experimental Study on the Influence of the Spread of Firebrand on Building Exterior Materials and Roofing Materials in Urban Areas (도심지 인접 산불의 불티 확산이 건축물 외장재와 지붕재에 미치는 영향에 관한 실험적 연구)

  • Min, Jeong-Ki
    • Journal of the Society of Disaster Information
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    • v.17 no.3
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    • pp.617-626
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    • 2021
  • Purpose: The purpose of this study is to evaluate the fire srpead risk of building exterior and roofing materials due to the firebrand of forest fire occurring in the urban areas. Method: In order to achieve this research purpose, by selecting building materials used for exterior and roofing materials of buildings, the time to ignition, total heat release, and heat release rate were investigated, and a forest fire firebrand system was established to the possibility of fire spread was confirmed. Result: As a result of the cone calorimeter test, the roofing material had a similar or faster ignition time due to radiant heat compared to the exterior material with the steel plate exposed to the outside, and showed a higher heat release rate and total heat release than the exterior material. Although it was affected by the flammable material, it was confirmed that it did not spread easily due to the limited amount of combustible material, and carbonization marks appeared inside. Conclusion: The cone calorimeter test method has been shown to be useful in understanding the combustion characteristics of building materials by radiant heat, but the fire spread due to a firebrand in a forest fire is directly affected by the flame due to the ignition of surrounding combustibles, so finding a direct correlation with the cone calorimeter method is difficult. It is judged that the roof material may be more vulnerable to the spread of fire due to the fire than the exterior material.

Development of the Surface Forest Fire Behavior Prediction Model Using GIS (GIS를 이용한 지표화 확산예측모델의 개발)

  • Lee, Byungdoo;Chung, Joosang;Lee, Myung-Bo
    • Journal of Korean Society of Forest Science
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    • v.94 no.6
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    • pp.481-487
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    • 2005
  • In this study, a GIS model to simulate the behavior of surface forest fires was developed on the basis of forest fire growth prediction algorithm. This model consists of three modules for data-handling, simulation and report writing. The data-handling module was designed to interpret such forest fire environment factors as terrain, fuel and weather and provide sets of data required in analyzing fire behavior. The simulation module simulates the fire and determines spread velocity, fire intensity and burnt area over time associated with terrain slope, wind, effective humidity and such fuel condition factors as fuel depth, fuel loading and moisture content for fire extinction. The module is equipped with the functions to infer the fuel condition factors from the information extracted from digital vegetation map sand the fuel moisture from the weather conditions including effective humidity, maximum temperature, precipitation and hourly irradiation. The report writer has the function to provide results of a series of analyses for fire prediction. A performance test of the model with the 2002 Chungyang forest fire showed the predictive accuracy of 61% in spread rate.

Establishment of the Method for Evaluating the Risk of Fire Spread to the Upper Floors due to Ejected Flame from an Opening in the Building Fires (건축물 화재시 개구분출화염으로 인한 상층부로의 화재확대 위험성평가 방법 구축)

  • Shin, Yi-Chul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.216-217
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    • 2020
  • As the fire inside the building grows rapidly, ejected flame from an opening occurs due to flashover. As a result, the number of cases where the flame spreads to the exterior of the building and rapidly expands to the upper floor is increasing. In particular, in the case of the fire in the Daebong Green Apartment, Uijeongbu in 2015, it was a case where the flame spread to adjacent buildings due to the opening eruption flame from the first ignited building, causing great damage to three apartments. Therefore, this study is to introduce an international standard under development that estimates the shape and properties of the ejected flame from an opening and quantitatively evaluates the radiant heat flux received by the exterior wall of the building by assuming the occurrence of the ejected flame from an opening.

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