• Journal of Power System Engineering
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• v.11 no.1
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• pp.51-55
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• 2007

A study on combustion characteristics using emulsified fuel in a diesel engine were performed experimentally. In this paper, the experiments were performed at engine speed 1800rpm, emulsion ratios were 0%, 10%, 20%, and main measured items were specific fuel consumption, cylinder pressure, rate of pressure rise, rate of heat release etc. The obtained conclusions were as follows. 1) Specific fuel consumption increased maximum by 19.8% at low load, but was not affected at full load. 2) Rate of pressure rise and rate of heat release were about the same in the case of 10% and 20% of emulsion ratio. 3) Cylinder Pressure increased 9.6%, rate of pressure rise increased 53.4% in case of emulsion ratio 20% at full load. 4) Rate of heat release increased 72.4% in case of emulsion ratio 20% at full load.

• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.1-8
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• 2008

This study was performed to evaluate the burning characteristics of wood-based materials and the effect of surface treatment of fire retardant using cone calorimeter. Four types of wood-based materials, such as Plywood, Oriented Strand Board (OSB), Particle Board (PB) and Medium Density Fiberboard (MDF), were tested at a constant heat flux of $50kW/m^2$ to investigate the time to ignition, mass loss rate, heat release rate, effective heat of combustion, etc. In addition, each type of wood-based material was tested at the same heat flux after fire retardant treatment on the surface to evaluate the effect of this treatment on the burning characteristics. The surface treatment of fire retardant, by the amount of $110g/m^2$, delayed the time to ignition almost twice. However, it was indicated that heat release rate, mass loss rate, and effective heat of combustion were not significantly affected by fire retardants treatment for all types of wood-based materials.

• Journal of the Korean Society of Combustion
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• v.19 no.4
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• pp.49-55
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• 2014

Design criterion for the size of micro Pt-catalytic combustor is investigated in terms of heat release rate. One-dimensional plug flow model is applied to determine the surface reaction constants using the experimental data at stoichiometric butane-air mixture. With these reaction constants, the mass fraction of butane and heat release rate predicted by the plug flow model are in good agreement with the experimental data at the combustor exit. The relationship between the size of micro catalytic combustor and mixture flowrate is introduced in the form of product of two terms-the effect of fuel conversion efficiency, and the effect of chemical reaction rate and mass transfer rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.129-135
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• 1995

This study aims to compare the heat release calculated using the ensemble average of pressure data with the heat release calculated using the least squares method for pressure data. This paper propose a heat release computation method that can analyze the most correct, straight and simple method to analyse combustion phenomenon. In conclusion, we found that the least squares method of third-order was the best computational method for heat release calculation.

• Fire Science and Engineering
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• v.22 no.5
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• pp.72-78
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• 2008

The mass loss rate and heat release rate of EPS sandwich panel cores were analysed using variable external irradiation level. The experimental materials were exposed to incident heat fluxes form 20 to 50 kW/$m^2$. For the measurement of mass loss rate and heat release rate, the size of specimen was $100mm{\times}100mm{\times}50mm$ and the samples were 3 different kinds. The combustion heat were carried out from the Oxygen bomb calorimeter and the mass loss rate and heat release rate were carried out from the Mass loss calorimeter according to ISO 5660-1. As the results of this study, the mass loss rate of Type A, B, and C were 2.7 g/$m^2s$, 2.8 g/$m^2s$, and 2.3 g/$m^2s$ and the heat release rate of Type A, B, and C were 58.23 kW/$m^2$, 47.19 kW/$m^2$, and 50.06 kW/$m^2$ respectively at the heat flux of 50 kW/$m^2$. In conclusion, when the heat release characteristics applied to a classification system of Canada, Type A and C can be classified grade C-3, and Type C can be classified grade C-2 from all data of this study.

• Fire Protection Technology
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• s.19
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• pp.22-28
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• 1995

The rate of heat release is probably the single most important measure of fire hazard. Several tech-niques were developed for the measurement of rate of heat release, but were not suitable for fire test-ing purpose. Recently the application of oxygen consumption principle made it possible to development of well-characterized heat release rate measurement apparatus, the furniture calorimeter for large-scale fire tests and the cone calorimeter for bench-scale fire tests. The cone calorimeter can be used to determine the ignitability as well as heat release rate and smoke development, mass loss rate, combustion gas production etc. from burning materials. Thus, test method using cone calorimeter, an internationally recognized and accepted for the evalua-tion of fire properties, is a very promising tool for combustion study on various kind of materials and products.

• Fire Science and Engineering
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• v.17 no.1
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• pp.76-84
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• 2003

This study was designed to investigate fire characteristics of the plastics insulating materials such as a polystyrene foam, polyurethane foam, and polyethylene foam, which is used an insulating materials i3t workplace. The fire characteristics of plastic insulating materials were carried out from the Cone Calorimeter test according to ISO 5660. The experimental materials used were commercial plastic insulating materials by products and their composition is not disclosed by the manufacturer. As the results of this study; the heat release rate of plastic insulating materials was increased with increasing density and heat flux. The peak heat release rate and the average heat release rate for the polyethylene foam in insulating materials were showed the highest, and the peak heat release rate for the polyethylene foam was the highest. The standard of heat release rate with a kind of products and heat flux of irradiance to prevent fire by plastic insulating materials was suggested.

• Fire Science and Engineering
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• v.17 no.4
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• pp.117-123
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• 2003

In this study; the ignition and heat release rate characteristics of rigid polyurethane foam were investigated in accordance with setchkin ignition tester and cone calorimeter which is using oxygen consumption principle. In the ignition temperature study; flash-ignition temperature was $383^{\circ}C$-$390^{\circ}C$, self-ignition temperature was$ 493^{\circ}C$∼495$^{\circ}C$. The self-ignition temperature of rigid polyurethane foam was about $100^{\circ}C$ higher than the flash-ignition temperature. In the cone calorimeter study, the time to ignition of rigid polyurethane foam was faster as the external heat flux increase. In the same heat flux level, the time to ignition was faster as the density of rigid polyurethane foam decrease. Also the heat release rate was the largest value at the heat flux of /$50 ㎾\m^2$ and had a tendency of increase as the heat flux level and density increase. In the standpoint of time to ignition and heat release rate, the fire performance of rigid polyurethane foam was influenced by the applied heat flux level and density and the flashover propensity classified by Petrella's proposal was high.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.18-25
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• 2002

Research to discuss the fire performance of materials requires tools for measuring their burning characteristics and validated fire growth models to predict fire behavior of the materials under specific tire scenarios using the measured properties as input for the models. In this study, burning characteristics such as time to ignition, weight loss rate, flame spread, heat release rate, total heat evolved, and effective heat of combustion for four types of wood-based materials were evaluated using the cone calorimeter and inclined panel tests. Time to ignition was affected by not only surface condition and specific gravity of the tested materials but also the type and magnitude of heat source. Results of weight loss rate, measured by inclined panel tests, indicated that heat transfer from the contacted flame used as the heat source into the inner part of the specimen was inversely proportional to specific gravity of material. Flame spread was closely related with ignition time at the near part of burning zone. Under constant and severe external heat flux, there was little difference in weight loss rate and total heat evolved between four types of wood-based panels. More applied heat flux caused by longer ignition time induced a higher first peak value of heat release rate. Burning characteristics data measured in this study can be used effectively as input for fire growth models to predict the fire behavior of materials under specific fire scenarios.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.11
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• pp.1486-1496
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• 2000

The initial flame kernel development and flame propagation in a constant volume combustion chamber is analyzed by the heat release rate and the mass fraction burnt. The combustion pressure is measured with a piezoelectric type pressure sensor. In order to evaluate the effects of ignition system and ignition energy on the flame propagation, four different ignition systems are designed and tested, and the ignition energy is varied by the dwell time. Several different spark plugs are also tested and examined to analysis the effects of electrodes on flame kernel development. The results show that the when the dwell time is increased, and when the spark plug gap is extended, heat release rate and the mass burnt fraction are increased. The materials and shapes of electrodes affect the flame development, because they change the energy transfer efficiency from electrical energy to chemical energy. The diameter of electrodes influences not only the heat release rate but also the mass burnt fraction as well.