• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.207-210
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• 2014

The potential of combustion treatment of low concentration VOC on a turbulent partially premixed flame has been studied experimentally. The significant decrease in hydrocarbon concentration from the low concentration VOC was observed with a turbulent partially premixed flame. The VOC/inert gas mixture whose fuel concentration is beyond the flammability limit could be treated in this method.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3270-3275
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• 2007

DME (Dimethyl Ether, $CH_3OCH_3$) has highly attracted attention as an alternative fuel for transportation, power generation and LPG substitute owing to its easy transportation and cleanliness. This study was conducted to verify the combustion performance and to identify potential problems when DME is fuelled to a gas turbine. GE7EA gas turbine of Pyong-Tak power plant was selected as a target to apply the DME. Combustion tests were conducted by comparing DME with methane, which is a major component of natural gas, in terms of combustion instability, $NO_X$ and CO emissions, and the outlet temperature of the combustion chamber. The results of the performance tests show that DME is very clean but has a low combustion efficiency in low load condition. From the results of the fuel nozzle temperature we have ascertained that DME is easy to flash back, and this property should be considered when operating a gas turbine and retrofitting a burner.

• Fire Science and Engineering
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• v.15 no.4
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• pp.1-9
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• 2001

The purpose of this study is to set up disaster prevention plan and risk assessment system considering combustion velocity at traditional housing zone. The combustion velocity analysis could contribute to build in disaster prevention technique through the potential risk analysis of the area, such analysis also able to set up comprehensive disaster prevention management system. Following results have achieved through the combustion velocity calculation. \circled1 The combustion velocity was calculated in order of the below winds, the above winds and the side winds. \circled2 It must be careful to set up disaster prevention plan in case of the below winds. \circled3 The combustion velocity was calculated at the density Bone where neighboring Distance and Length was small. \circled4 It proved that factors of each parameter not mostly effect to analyse the combustion velocity in limit of the 30 minutes after ignition. \circled5 At the density zone where Distance and Length is small the duration of transfer to neighboring house takes up to 4 minutes, it is required to set up of emergency response plan to minimize the fire dispersion.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.1
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• pp.30-39
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• 2017

Interests in fuel cell based power generation systems are on the steady rise owing to various advantages such as high efficiency, ultra low emission, and potential to achieve a very high efficiency by a synergistic combination with conventional heat engines. In this study, the performance of a hybrid system which combined a molten carbonate fuel cell (MCFC) and an indirectly fired micro gas turbine adopting carbon dioxide capture technologies was predicted. Commercialized 2.5 MW class MCFC system was used as the based system so that the result of this study could reflect practicality. Three types of ambient pressure hybrid systems were devised: one adopting post-combustion capture and two adopting oxy-combustion capture. One of the oxy-combustion based system is configured as a semi-closed type, while the other is an open cycle type. The post-combustion based system exhibited higher net power output and efficiency than the oxy-combustion based systems. However, the semi-closed system using oxy-combustion has the advantage of capturing almost all carbon dioxide.

• Journal of the Korean Society of Combustion
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• v.9 no.1
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• pp.11-17
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• 2004

The purposes of this study are to analyze nitrogen oxides(NOx) formation mechanism and to reduce abnormal NOx emissions in gas turbines. Industrial gas turbines emissions have potential to negative affect to the atmosphere in many different ways such as photochemical smog, acid rain and global warming. In conventional gas turbine combustors, one of the main pollutants such as nitrogen oxide(NOx) species, are principally formed from combustion process of fuel with oxygen in the primary combustion zone, and their emission levels are highly depend on peak temperatures in the combustor. In order to examine the characteristics and the effect of NOx formation, we used gas turbine of which commercial operating in Korea. From the examination, it has been found that NOx emissions are relatively high at low load(output) and during combustion mode change. Also, the effect of Air/Fuel ratio was considered. As the Air/Fuel ratio was increased in Lean-Lean mode, the NOx emission was decreased. The results of this study indicated that NOx emission levels are highly depend on peak temperature and pressure of combustion process in the combustor.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.5 s.248
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• pp.465-471
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• 2006

Controlled auto-ignition(CAI) combustion, offers the potential to improve fuel economy and reduce emission simultaneously. In this study, CAI-combustion was achieved in a single cylinder gasoline DI engine with modified camshafts in order to restrict the gas exchange process. We investigated the effects of air-fuel ratio, residual EGR rate and injection timing such as early injection and late injection on the attainable CAI combustion region. The effect of injection timings on combustion characteristic such as start of combustion, combustion duration and heat release rate was also investigated. From the result early injection causes the mixture to ignite earlier and burn more quickly due to the exothermic reaction during the recompression and gives rise to good mixing of the fuel/air. On the other hand, late injection extended the operation region more than early injection but the emissions of HC and NOx were more or less increased than early injection.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3288-3293
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• 2007

Compressed natural gas has good potential for alternative vehicle fuel due to its economical and clean characteristics. However, the composition of natural gas based on production location is known to affect performance and emissions of CNG engine. Thus, the objective of this paper is to clarify the effect of fuel composition on combustion and emissions of CNG engine. This paper presents combustion characteristics obtained from running a 2.5L, 4-cylinder CNG engine retrofitted IDI diesel engine with engine dynamometer. BSFC, emissions, fuel consumption and combustion pressure were measured under steady state operating conditions especially at partial load for CNG engine. Based on the experimental results, we found that CNG composition affects engine performance, fuel conversion efficiency and burning rate.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.541-549
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• 2003

A basic experimental study was conducted in order to find the optimum combustion control technology to decrease the thermal NO$_{x}$, by applying the catalytic combustion method with natural gas. NO$_{x}$ emission increased with increasing space velocity due to temperature rising in the furnace. In order to overcome the low resistance to high temperature, secondary air was supplied to the CST combustor. The following secondary fuel formed combustible mixture in part, which resulted in steep increase of the exiting temperature of the 2nd catalyst bed. It led to the more generator of NO$_{x}$, 30∼60% of the 1 st catalyst bed. It might be due to the potential increase of thermal NO$_{x}$.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.61-64
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• 2017

The gas-generator open cycle is adapted for liquid rocket engine of Korea Space Launch Vehicle-II. The combustion instability can interfere with combustion performance and cause a noise and vibration or carry the potential for serious damage. This study introduces the experience cases of combustion instability in development of the gas generator for liquid rocket engine.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.11
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• pp.2159-2168
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• 1992

Coal-water slurry is considered to have the potential for displacing petroleum used in the existing oil-fired industrial and utility boilers. The combustion of coal-water slurry(CWS) is a complex process and little is known about the detailed mechanism. In this paper the combustion behavior of a single suspended droplet of CWS in hot gas stream was investigated. The effect of coal particle size, water content in droplet, initial droplet size, ambient temperature and oxygen fraction in ambient gas were studied. The results are as follows; (1) Increasing the oxygen fraction in ambient gas considerably reduced the char combustion time. (2) The variation of water content and coal particle size in droplet showed little effect on the combustion behavior. (3) In the relatively high temperature ambient gas, the water evaporation time became shorter and the combustion process was stable.