• Journal of the Society of Disaster Information
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• v.18 no.2
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• pp.280-289
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• 2022

Purpose: In this study, the characteristics of fire occurrence according to ignition heat sources such as operating equipment, cigarette/lighter fire, and flame/fire were analyzed. Method: One-way ANOVA and cross-analysis were used to analyze the characteristics of fire occurrence by verifying the difference between the ignition environment, fire damage status and scale, and cause of ignition according to the ignition heat source. Result: The fire occurrence characteristics were analyzed through As a result of the analysis, it was found that fires caused by operating devices occurred more frequently on weekdays than other ignition heat sources, and the number of victims and the number of victims were the highest, so mobilization of firefighting power and property damage were the greatest. The initial ignition was generated by electric and electronic devices, and the combustion was expanded by the synthetic resin. For fires caused by cigarette and lighter fires, the most fires occurred on Saturdays and Sundays, and the mobilization of the police force was more characteristic than the mobilization of the firefighting force. In particular, it was found that the initial ignition and combustion expansion were caused by paper, wood, and hay. Fires caused by sparks and sparks occurred most frequently on Saturdays and Sundays, and initial ignition and combustion expansion were found to be caused by paper, wood, and hay. In particular, it showed the characteristic that it occurred in the place farthest from the fire station. The common characteristic of all ignition heat sources was that the fire occurred most frequently in the afternoon time, and the fire type was predominantly the building structure fire, and only the ignition point was burned the most. Conclusion: In order to prevent fire and minimize damage, it is necessary to analyze the tendency of fire occurrence and to prepare appropriate preparations according to the fire occurrence factors. In order to analyze the characteristics of fire occurrence using public data in the future, it is necessary to standardize disaster data and to open and activate data.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.3
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• pp.60-65
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• 1988

The ignition characteristics of repetitive electric sparks into a quiescent acetylene-air premixture and LPG-argon-air premixture was investigated by using a home-made Repetitive-Spark-Generator(RSG) to elucidate the effect of fuel burning velocity to ignition ability of RSG. Results show that the optimum spark delay time interval is strongly related with fuel burning velocity, or implicitly with characteristic reaction time scale of each fuel.

• Bulletin of the Korean Chemical Society
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• v.18 no.10
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• pp.1071-1075
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• 1997

Detonation characteristics of acetylene were studied behind reflected shock waves in the temperature range 800-1350 K by monitoring OH emission and pressure profiles. For a comprehensive measurement of ignition delay time, the mixture composition was varied in a wide range of Ar mole % was varied from 0.625 to 2.5 in stoichiometric ratio of C2H2-O2-Ar. A computer simulation study was also performed to elucidate the important elementary steps determining ignition behavior. The 33-reaction mechanism provides a good agreement in delay time between the observed and the calculated ones.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.37-43
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• 2010

The purpose of this paper is to investigate the effect of air-fuel ratio on the combustion and emissions characteristics of spark ignition (SI) gasoline engine fueled with bio-ethanol. A 1.6L SI engine with 4 cylinders was tested on EC dynamometer. In addition, lambda sensor and lambda meter were connected with universal ECU to control the lambda value which is varied from 0.7 to 1.3. The engine performance and combustion characteristics of bio-ethanol fuel were compared to those obtained by pure gasoline. Furthermore, the exhaust emissions such as carbon monoxide (CO), unburned hydrocarbon (HC), oxides of nitrogen ($NO_X$) and carbon dioxide ($CO_2$) were measured by emission analyzers. The results showed that the brake torque and cylinder pressure of bio-ethanol fuel were slightly higher than those of gasoline fuel. Brake specific fuel consumption (BSFC) of bio-ethanol was increased while brake specific energy consumption (BSEC) was decreased. The exhaust emissions of bio-ethanol fuel were lower than those of gasoline fuel under overall experimental conditions. However, the specific emission characteristics of the engine with bio-ethanol fuel were influenced by air-fuel ratio.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.620-627
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• 2019

In this study, ignition delay characteristics of various bio aviation fuels (Bio-ADD, Bio-6308, Bio-7720) produced by HEFA process using different raw materials were compared and analyzed. In order to confirm the feasibility of applying bio aviation fuel to actual system, ignition delay characteristics of petroleum-based aviation fuel (Jet A-1) and blended aviation fuel (50:50, v:v) also analyzed. Ignition delay time of each aviation fuel was measured by using CRU, surface tension measurement and GC/MS and GC/FID analysis were performed to interpret the results. As a result, ignition delay time of Jet A-1 was the longest at all temperature because it contains aromatic compounds about 22.8%. The aromatic compounds can produce benzyl radical which is thermally stable and has low reactivity with oxygen during decomposition process. In the case of bio aviation fuels, ignition delay times were measured similarly because the ratio of n-paraffin/iso-paraffin constituting each aviation fuel is similar (about 0.12) and the composition ratio of cycloparaffin also has no difference. In addition, ignition delay times of blended aviation fuels (50:50, v:v) were measured close to the mean value those of each fuel so it was confirmed that it can be applied without any changing or improving of existing system.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.336-343
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• 2017

Intake air conditions, such as air temperature, pressure, and humidity, are very important parameters that influence engine performance including combustion and emissions characteristics. The purpose of this study is to investigate the effects of intake air temperature on combustion and exhaust emissions characteristics in a single cylinder diesel engine. In this experiment, an air cooler and a heater were installed on the intake air line and a gas flow controller was installed to maintain the flow rate. It was found that intake air temperature induced the evaporation characteristics of the fuel, and it affects the maximum in-cylinder pressure, IMEP(indicated mean effective pressure), and fuel consumption. As the temperature of intake air decreases, the fuel evaporation characteristics deteriorate even as the fuel temperature has reached the auto-ignition temperature, so that ignition delay is prolonged and the maximum pressure of cylinder is also reduced. Based on the increase in intake air temperature, nitrogen oxides(NOx) increased. In addition, the carbon monoxide(CO) and unburned hydrocarbons(UHC) increased due to incomplete fuel combustion at low intake air temperatures.

• Journal of the Korean Society of Combustion
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• v.15 no.4
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• pp.65-73
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• 2010

In order to provide fundamental information for developing reaction model in the practical blended coal power plants, effects of particle size and blending ratio on combustion characteristics and thermal reaction in co-firing with bituminous and sub-bituminous coals were experimentally investigated using a TGA and a laboratory-scale burner. Characteristic parameters including ignition, burnout temperature and activation energy were determined from TG and DTG combustion profiles. Distributions of flame length and mean particle temperature were investigated from the visualization of flames in slit-burner system. As coal particle size decreased and volatile matter content increased, characteristic temperatures and activation energy decreased. The ignition/burnout characteristics and activation energy are linearly influenced by a variation in particle size and blending ratio. These results indicated that the control of the coal blending ratio can improve the combustion efficiency for sub-bituminous coals and the ignition characteristics for bituminous coals.

• Journal of Power System Engineering
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• v.19 no.2
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• pp.49-56
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• 2015

As an alternative fuel that can be used in SI engine, LPG is one of clean fuels with larger H/C ratio compared to gasoline, low $CO_2$ emission, and small amount of pollutants such as sulfur compounds. When LPG is used in spark ignition engine, volumetric efficiency of the engine can be improved and pumping loss can be reduced by performing direct injection into the combustion chamber instead of port fuel injection. LPG-DI engine allows for lean combustion and stratified combustion under low load. In case of stratified combustion, air fuel ratio can be greatly increased compared to theoretic mixture ratio combustion. Improved thermal efficiency of the engine and reduced pumping loss can be expected from stratified combustion. Accordingly in this study, an experimental apparatus for visualization was designed and manufactured to study the combustion process of LPG after injection and ignition, intended to examine ignition probability and combustion characteristics of spark ignition direct injection(SIDI) LPG fuel. Ambient pressure, ambient temperature and fuel injection pressure were found as important variables that affect ignition probability and flame propagation characteristics of LPG-air mixture. Also, it was verified that the injected LPG fuel can be directly ignited by spark plug under appropriate ambient conditions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.27 no.1
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• pp.64-68
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• 1991

In this paper, to percuss whether fish oil can substitute for marine fuel oil, the characteristics on the evaporation and ignition of 3 fish oils, Sardine oil, File fish oil and Alaska pollac oil, were investigated experimentally by suspending single fish oil droplel in hot atmosphere, and experiments on methanol and light oil were also carried out to compare the characteristics. The results abtained are summarized as follow; 1) Evaporation and ignition phenomena on the methanol and light oil by the present experimental method agreeded with the results of the earlier investigation. 2) The characteristic on evaporation and ignition of all 3 fish oils took the same pattern; in late stage of evaporation at atmospheric Temperature 55$0^{\circ}C$ droplet rapidly expanded and contracted, and then remained solid corbide, but in case of $650^{\circ}C$ rapidly expanded and ignitied, and then completly burned non-remained solid carbide. 3) As fish oil mixed with light oil (50% weight), in beginning stage of evaporation droplet depended on the characteristics of light oil, but in end stage depended on fish oil. 4) Ignition temperature of fish oil droplets was about 47$0^{\circ}C$, higher than about 25$0^{\circ}C$ of light oil, but atmospheric temperature to ignite droplet was about $650^{\circ}C$, lower than about 75$0^{\circ}C$ of light oil.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.137-142
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• 2008

Ignition characteristics of combustion chamber with LOx lead cyclogram for liquid rocket engine were described. The combustion chamber has chamber pressure of 60 bar, propellant mass flow rate of 89 kg/s, and nozzle expansion of 12. Cold flow test to determine the filling time of propellant for cyclogram with LOx lead supply, ignition test to check the ability to ignite starting fuel from the ignitor, low pressure combustion test to check the propagation of flame into main fuel-oxidizer mixture from starting fuel and the main combustion stage, and design point combustion test to check the combustion performance were performed. Ignition and combustion tests with LOx lead supply were successfully performed and the stable cyclogram of start sequence for combustion chamber was developed.