• Title/Summary/Keyword: flame spread rate

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A Study on the fire characteristic of pipe insulation film materials (배관 보온필름의 화재특성에 관한 연구)

  • Lee, Young-Sam;Lee, Jang-Won;Rie, Dong-Ho
    • Journal of the Korea Safety Management & Science
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    • v.14 no.2
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    • pp.65-70
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    • 2012
  • This study was performed to test the combustive properties of the pipe insulation materials which are mainly used in the industries and buildings. Fire characteristic test of pipe insulation film according to the KS F ISO 5660-1 was performed. The experimental materials commonly used in the pipe insulation were used four kinds of films. Two kinds of 4 types of products that have the flame retardant performance and the other two types of them have no flame retardant performance. They were selected for fire characteristic test. The result of finding 25kW/$m^2$ radiation from the ignition was that flame retardant products were 140sec and the other one were 69sec in average of heat release rate(HRR). The result of flame retardant products in the 50kW/$m^2$ was 34sec and the other one were 15sec in average of HRR. However, the HRR of flame retardant products was much higher than the other one. Flame propagation test was conducted according to the KOFEIS 1001. The result of flame retardant products was that flame retardant products had a hold without fire spread after firing them. But the other one were completely fired after firing them. Therefore, I want to recommend that flame retardant products need to be used by the regulation to prevent or decrease a fire spread.

A Fire Hazard Assessment of Interior Finish Materials (건물 내장재의 화재위험성 평가 방법)

  • 김운형
    • Fire Science and Engineering
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    • v.12 no.2
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    • pp.17-28
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    • 1998
  • To propose a new fire hazard assessment criteria of interior finish materials, the properties and incident heat flux of interior finish materials in a compartment fires are investigated and compared by using flame spread model developed by Quintiere. The properties considered on which fire growth depend are including flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. ISO Room Corner Test(9705) is applied in the model and the time for total energy release rate to reach 1MW is examined. The results are compared for the 24 different materials tested by EUREFIC. Dimensionless parameter a, b and ${\gamma}$b are used to develope a new method in which fire hazard of interior finish materials can be classified resulting from correlation between b and flashover time. Results show that if b greater than about zero, flashover time in the ISO Room-Corner Test is principally proportional to ignition time only.

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APPLICATIONS OF A MODEL TO COMPARE AFLAME SPREAD AND BEAT RELEASE PROPERTIES OF INFERIOR FINISH MATERIALS IN A COMPARTMENT

  • Kim, Woon-Hyung;James G. Quintiere
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.193-200
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    • 1997
  • Flame spread and heat release properties and incident heat flux of interior materials subject to an igniter heat flux in a compartment are investigated and compared by using computer model. A comer fire ignition source is maintained for 10 minutes at 100 kw and subsequently increased to 300kw. In executing the model, base-line material properties are selected and one is changed for each run. Also 4 different igniter heat flux conditions and examined. Results are compared for the 12 different materials tested by the ISO Room Comer Test (9705). The time for total energy release rate to reach 1MW is examined. The parameters considered include flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. The model can show the importance of each property in causing fire growth on interior Hnish materials in a compartment. The effect of ignitor heat flux and material property effects were demonstrated by using dimensionless parameters a, b and Tb. Results show that for b greater than about zero, flashover time in the ISO Room-Corner test is principally proportional to ignition time and nothing more.

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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.

Study on Flame Height Equation for the Pinus densiflora Surface Fuel Bed (소나무 낙엽층 화염높이 산정식에 관한 연구)

  • Kim, Dong-Hyun
    • Fire Science and Engineering
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    • v.23 no.6
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    • pp.10-15
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    • 2009
  • Flame height calculation in a forest fire is a crucial part of predicting horizontal or vertical flame spread flared by radiation heat transfer. Flame height, which is one of the flame characteristics, can be estimated by the average height of luminous flame. This research relied on flame height observation test on P. densiflora surface fuel bed, which are surface combustibles in a forest, and calorimeter to measure Heat Release Rate, thus produced $H_f=0.027(\dot{Q'})^{2/3}$, flame height calculation equation for surface fuel. The research did not take into consideration such conditions as external velocity, slope and other variables that could affect flame height. According to comparison among experiment results, calculation results of the above formula and those of existing Heskestad formula (1998), it was found that standard error in fallen pine needles between experimental results and calculation results of the above formula amounts to 0.08, whereas standard error in same plant between experimental results and calculation results of existing Heskestad formula amounts to 0.23.

Experimental Study on the Effects of AC Electric Fields on Flame Spreading over Polyethylene-insulated Electric-Wire (폴리에틸렌으로 피복된 전선화염의 전파에 교류전기장이 미치는 영향에 관한 실험적 연구)

  • Jin, Young-Kyu;Kim, Min-Kuk;Park, Jeong;Chung, Suk-Ho;Kim, Tae-Hyung;Park, Jong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.11
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    • pp.1015-1025
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    • 2010
  • In this present study, we experimentally investigated the effects of electric fields on the characteristics of flames spreading over electric-wires with AC fields. The dependence of the rate at which a flame spreads over polyethylene-insulated wires on the frequency and amplitude of the applied AC electric field was examined. The spreading of the flame can be categorized into linear spreading and non-linearly accelerated spreading of flame. This categorization is based on the axial distribution of the field strength of the applied electric field. The rate at which the flame spreads is highly dependent on the inclined direction of the wire fire. It could be possible to explain the spreading of the flame on the basis of thermal balance.

Evaluation of Heat Loss by Means of Plasma Jet Ignition during Combustion Duration in the Constant Volume Vessel (정적연소실내에서의 플라즈마 제트 점화에 대한 연소기간중의 열손실산정)

  • 김문헌;문경태;박정서;김홍성
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.2
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    • pp.96-103
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    • 2003
  • In this paper, the heat loss to the constant volume vessel wall was investigated using instantaneous heat flux sensor, schlieren visualization, pressure rise curve. And the heat loss characteristics of plasma jet ignition were compared with conventional spark ignition. In case of plasma jet ignition, the flame kernel moves toward the center of combustion vessel in the initial period of combustion, and the flame surface spread out to the vessel wall. However, in case of conventional spark ignition, the flame surface contact with combustion vessel wall in the initial period of combustion. As a result, heat loss in the combustion duration for conventional spark ignition increase faster than that of plasma jet ignition. And the combustion enhancement rate of plasma jet ignition is higher than that of conventional spark ignition, and it was found that the heat loss rate is inversely proportional to the combustion enhancement rate.

A Study on the Fire Spread Risk of Resident Buildings With Pilotis (필로티 건물 이격거리에 따른 화재확산 위험성 연구)

  • Choi, Seung-Bok;Choi, Doo-Chan;Choi, Don-Mook
    • Fire Science and Engineering
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    • v.31 no.4
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    • pp.103-110
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    • 2017
  • With the common tendency in the accordance with the trend, low-stories built edifices that are Pilotis-oriented structured exponentially and constantly increasing its number of buildings. It inevitably contains its risks of facing conflagrations as most of its part is used as parking lots. In the parking lots, the length of the flame has a heavy-weighted possibility that it would get increased because the heat release rate gets relatively high due to the vehicle insulation. Following on top of that, due to the nature of the Pilotisconsisting of pillars, there is a risk of flame spread to the adjacent building if the same Pilotis-structured buildings are adjacent to each other, if the flame spreads to the surroundings due to the influence of the wind. Because the most of the pilotis-structured-buildings have this entrance that makes the residents be able to enter, if the entrance were plugged the resident get a serious risk of a poisonous gas and a flame. Therefore, if the parking-lots of the pilotis-structured-buildings are adjacent to each other it requires a space to prevent the place from the spread of flame. This research studied how far is appropriate to prevent flame spreading with FDS. As a result, the study found that the distance at least 3.0 m is required.

Study on the Combustion Characteristics of Flammable materials and Combustion Accelerants in an Arson (방화 범죄에서 가연성 물질과 연소촉진제의 연소 특성에 관한 연구)

  • Park, Hye-Jeong;Nam, Ki-Hun;Kim, Kwang-Il
    • Fire Science and Engineering
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    • v.31 no.5
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    • pp.7-11
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    • 2017
  • The purpose of this study is to recognize the necessity for the management of the available materials in cases of arsons and to prevent arson gaining an understanding of the combustion characteristics of the flammable materials and combustion accelerants in arson cases. We investigated and analyzed the statistical data on arsons and selected flammable materials (wood, paper, synthetic textiles, synthetic resins), and combustion accelerants (gasoline, diesel, solvent) that are frequently used in cases of arson. We conducted a thermogravimetric analysis to assess the thermal properties of the flammable materials. Also, we conducted burning and flame spread rate tests for the purpose of comparing and analyzing the combustion characteristics of the flammable materials and combustion accelerants.

A Study on Smoke Movement in Room Fires with Various Pool Fire Location

  • Jeong, Jin-Yong;Ryou, Hong-Sun
    • Journal of Mechanical Science and Technology
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    • v.16 no.11
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    • pp.1485-1496
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    • 2002
  • In order to investigate the fire-induced smoke movement in a three-dimensional room with an open door, numerical and experimental study was performed. The center, wall, and corner fire plumes for various sized fires were studied experimentally in a rectangular pool fire using methanol as a fuel. The numerical results from a self-developed SMEP (Smoke Movement Estimating Program) field model were compared with experimental results obtained in this and from literature. Comparisons of SMEP and experimental results have shown reasonable agreement. As the fire strength became larger for the center fires, the air mass flow rate in the door, average hot layer temperature, flame angle and mean flame height were observed to increase but the doorway-neutral-planeheight and the steady-state time were observed to decrease. Also as the wall effect became larger in room fires, the hot layer temperature, mean flame height, doorway-neutral-planeheight and steady-state time were observed to increase. In the egress point of view considering the smoke filling time and the early spread of plume in the room space, the results of the center fire appeared to be more dangerous as compared with the wall and the corner fire. Thus it is necessary to consider the wall effect as an important factor in designing efficient fire protection systems.