• Fire Science and Engineering
• /
• v.24 no.5
• /
• pp.115-121
• /
• 2010

This study was performed to test the combustive properties of Pinus rigida-based materials by the treatment of ammonium salts. Pinus rigida plate was soaked in three 20 wt% ammonium salt solutions such as ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). Comparing with virgin pinus rigida plate, specimens treated with the ammonium salts had lower combustive properties and It is supposed that the combustion-retardation properties improved due to the treated ammonium salts in the virgin Pinus rigida. Also, the specimens with treated ammonium salts showed both the lower peak heat release rate (PHRR) and lower total heat release (THR) than those of virgin plate.

• Fire Science and Engineering
• /
• v.23 no.4
• /
• pp.25-31
• /
• 2009

With rapid growths of economy and technology, structures and forms of buildings have been diversified and complicated. Buildings also have become higher and larger than ever before. As a result, more people use a building and more combustibles exist in the building. Without understanding of combustion characteristics and the establishment of a fire safety plan in case of a residential fire, it is expected great loss of lives and properties. In this study, experiments were carried out to promote an understanding of the combustion characteristics of combustibles in the building. Sofa and bed were used as combustibles in the experiment. Heat release rate of the sofa was about 1.9MW. Heat release rate of the bed was approximately 650kW.

• Fire Science and Engineering
• /
• v.16 no.4
• /
• pp.77-84
• /
• 2002

In this paper, we had analyzed comsbustion gases using a GASTEC colorimetric gas detector tube according to the method of NES 713 in order to combustion gases toxicity evaluation for beads polystyrene foam, extruded polystyrene foam, rigid polyurethane foam, flexible polyurethane foam, flexible polyvinyl chloride pipe, vinyl floor cover, polyethyelene foam(flame retardant untreated) and polyethyelene foam (flame retardant treated) of plastics material. As results of gas analyses by using this method, comsbustion gases producted from small specimens of plastics material had reached fatal to man at 30 minutes exposure time that had possesed toxicity index of more than 1. Toxicity indexes of each specimen were estimated range of 4.3∼179.2, flexible polyvinyl chloride showed the hightest toxicity index at 179.2, and beads polystyrene foams showed the lowest toxicity index at 4.3.

• Fire Science and Engineering
• /
• v.33 no.5
• /
• pp.48-54
• /
• 2019

A Large Eddy Simulation (LES), adopting the Eddy Dissipation Concept (EDC) 1-step model, was successfully performed for backdraft phenomena. The activation energy of the finite chemistry reaction in the EDC 1-step model was adjusted to simulate the backdraft. The prediction of the EDC 1-step model was similar to that of the Mixing-Controlled Fast Chemistry (MCFC) model, except when the backdraft occurred. The EDC 1-step model could be used to simulate the experimental peak pressure, but not the first peak pressure of the backdraft.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.1
• /
• pp.345-350
• /
• 2017

Downsizing is widely applied to diesel engines in order to improve fuel efficiency and reduce exhaust emissions. Engine sizes are becoming smaller but pressure and temperature inside combustion chambers are increasing. Therefore, research for fuel spray under high pressure and temperature conditions is important. A constant volume chamber which simulates high temperature and pressure likely to be found in diesel engines was developed in this study. Pressure and temperature were increased abruptly because of ignition of the pre-mixture in the constant volume chamber. Then pressure and temperature were gradually decreased due to the heat loss through the chamber wall. Fuel spray occurred when temperature and pressure were reached at the target condition. In this experiment, the temperature condition should be exactly defined to understand the relation between fuel evaporation and ambient temperature. A fast response thermocouple was developed and used to measure the temporal and spatial temperature distribution during the combustion process inside the combustion chamber. In the results, the core temperature was slightly higher than the bulk temperature calculated by the gas equation. Ed-note: do you want to say 'ideal gas equation'? This was attributed to the heat transfer loss through the chamber wall. The vertical temperature deviation was higher than the horizontal temperature deviation by 5% which resulted from the buoyancy effect.

• Fire Science and Engineering
• /
• v.22 no.3
• /
• pp.258-264
• /
• 2008

This study proposes the experimental methods which shows various guidelines for systematic study of surface forest fuels. The thermal characteristics of surface fire fuels such as Quercus Variabilis and Pinus Densiflora fallen leaves are measured using TGA and Oxygen Bomb Calorimeter. Both of them are common species of Korean forest. Also the combustion characteristics of surface fire fuels are analysed according to the methods which are commonly used in Pool Fire analysis. The measured parameters are gas velocity, temperature, flame height, heat release rate and mass loss rate. A system is designed to simulate the surface fire. Methods and results are shown for the application of forest fire study.

• Fire Science and Engineering
• /
• v.14 no.2
• /
• pp.7-13
• /
• 2000

We had investigated thermal stability, Ignition temperature and fire gas for polyurethane foams used for manikin, cushion and interior finishing material. Decomposition of polyurethane foams with temperature was investigated using a DSC and the weight loss with temperature increase using a TGA in order to find the thermal hazard of polyurethane foams, and the ignition temperature of polyurethane foams according to species. We studied constant temperature among ignition temperature measuring methods. In addition, noxious gases for polyurethane foams according to combustion condition were analyzed using gas analyzer and GASTEC. As results, initial decomposition temperature of polyurethane foam used for interior finishing material was lower than those for manikin and cushion, and exothermic energy was higher. Ignition temperature of polyurethane foam of interior finishing material was $420^{\circ}$. All of combustion forms at $427^{\circ}$ and under were smoldering combustion, and it was combustion at $500^{\circ}$. As furnace temperature was increased, concentration of noxious gases such as carbon oxide, carbon dioxide, and hydrogen cyanide was increased. And nitrogen oxide at combustion condition($500^{\circ}$) was over 10 ppm.

• Fire Science and Engineering
• /
• v.28 no.4
• /
• pp.64-72
• /
• 2014

Flammable liquids residues in fire debris and pyrolysis products of flammable materials were analyzed by using Gas detecting tube, Gas Chromatograph/Mass Spectrometers (GC/MS), and Pyrolyzer. Comparison studies between chemical components detected in debris fired with and without Flammable liquids were performed. Though Flammable liquids were not present in debris, Gas detecting tube colors were also changed. Chemical components produced from conventional combustions were different from those produced from pyrolysis. Due to the difference of the reaction conditions between combustions and pyrolysis, different chemical products were produced. Petrochemical products of PVC wood-linoleum block could produce ignitable chemicals, such as toluene, ethylbenzene, undecane, and dodecane. So, for better fire investigation more consideration of those chemicals will be porformed.

• Fire Science and Engineering
• /
• v.28 no.4
• /
• pp.14-20
• /
• 2014

The purpose of this study is to analyze combustion patterns by filling a specific container with a flammable liquid and performing combustion tests in a divided space. The container used for the test is made of plastic, 20 mm in depth and 150 mm in width. After the liquid was ignited, its combustion process was photographed using a digital camera and video camera. It was found that in the case of benzene, the flame reached its peak at the fastest speed about 60 s while in the case of alcohol, the flame reached its peak at the lowest speed about 360 s, which is approximately six times slower than the benzene. In most cases, when the flame reached its peak, smoke generated was dark as the plastic container and flammable liquid were combusted simultaneously. After completion of the combustion, it was possible to sample oil vapor from all flammable liquids excluding soybean oil as a result of the examination of oil vapor using a crime investigation tube. That is, it can be seen that there is significant difference in flame propagation speed, pattern, etc., depending on the combustible substances.

• Fire Science and Engineering
• /
• v.25 no.3
• /
• pp.1-7
• /
• 2011

This paper studied analysis of deflagration rapid propagation of burning through only a few second and fire cause into the Busan indoor shooting range. We carried out combustion experiment of sound-absorbing materials extensively used, to analyze propagation path of burning in indoor shooting range. From the experimental results, general sound-absorbing materials were rapid burned simultaneously with ignition and in case of attached gunpowder residue, they were burning about tripled by comparison with general sound-absorbing materials. The incombustibility sound-absorbing materials had all gone out simultaneously with ignition, but they were burning similar to general type materials in case of attached gunpowder residues. In order to analysis of the cause of fire, we calculated kinetic energy of bounced off bullet, from result, if the bounced off bullet impacted gunpowder residues, the gunpowder residues were possible to ignite by the bullet.