• Journal of the korean Society of Automotive Engineers
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• v.12 no.3
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• pp.63-70
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• 1990

In a premixed flame stabilized by a streamlined step, the flame structure and combustion characteristics were investigated to identify the effect of the pressure pulsation in a combustion air. A flame stabilizing limits, visualization, mean temperature, ion current and gas concentration (O$_{2}$, CO$_{2}$, CO, UHC) were measured. With the combustion air of higher pressure pulsation, the development of the mixing layer was fast and wide, the temperature and combustion intensity were higher at arbitrary section. But, the effect was notably decreased with X=150 mm downstream. And a first eddy formation from step edge was earlier. Thus, with the combustion air of higher pressure pulsation, high rate of heat generation was expected.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.269-273
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• 2014

The objective of this study is to safety assessment for human body on the guided missile combustion products. This study is to verify the safety assessment when operating the interior missile ejection take on verify the safety of the human body. During the missile ejection of combustion products, this study is analyzed combustion products. Result are accepted NIOSH and KOSHA of the safe guideline, and 6 exposure gas to the specified values 42% (CO), 22% ($CO_2$), not detected (others) are within minimal exposures criteria of the reference value respectively. Contribution of these results supported that interior missile ejection during combustion products may have been ensured human safely. Therefore, the future for improving the environmental safety of the shooting projectile steel plate round, dust collector, ventilation and other facilities is to improve environmental safety and efficient renovated design needed by target focused areas.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.309-311
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• 2015

The MILD(Moderate or Intense Low-oxygen Dilution) combustion has been considered as one of the promising combustion technology for high thermal efficiency and low emissions. In this paper, the effect of fuel oxygen impingement on formation of MILD combustion was analyzed using numerical simulation. This investigation was simulated under the thermal intensity $0.04MW/m^3$ and equivalence ratio 0.91. The results show that the temperature distribution was become relatively uniform and the amount of CO emission was decreased as the increase of oxygen jet velocity and impinging angle.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.1
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• pp.177-188
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• 1987

A compute program based on the minimization of total Gibbs' free energy and enthalpy balance was developed to calculate the chemical equilibrium composition and adiabatic flame temperature, especially stressed on NO and CO concentration of Heavy oil. Twenty four components of combustion gases which would be produced from the combustion of Heavy oil were chosen and utilized for the products composition analysis of competing combustion reaction. As the results, following conclusions were turned out; (1) Maximum adiabatic flame temperature was found around to be 2900K, when the stoichiometric air ratio was 0.8. (2) Maximum NO quantity in adiabatic process was occurred when supplied air quantity was around 120% of theoretical air requirement. (3) NO and CO quantities were increased with combustion gas temperature at constant stoichiometric air ratio. (4) At constant temperature of combustion gas, NO quantity was increased and Co quantity was decreased with supplied air quantity.

• Journal of the Korean Society of Combustion
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• v.9 no.1
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• pp.25-31
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• 2004

Various types of the air/fuel pre-mixer have been designed and tested to investigate the combustion characteristics of the lean-premixed gas turbine combustor, such as NO emission and flame stability. One type of the pre-mixers has been selected and installed to a 70 kW lean-premixed gas turbine combustor. The concentrations of CO and NO were measured with varying equivalence ratios in the combustion chamber at ambient pressure. The result shows that the emissions of CO and NO are heavily affected by the shape of the pre-mixer. The NO and CO emissions decreased, as the mixing ratio of air and fuel increased. In addition, the NO emission of the lean-premixed low NOx combustor is more dependent on the equivalence ratio than that of the conventional combustor.

• Clean Technology
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• v.25 no.4
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• pp.316-323
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• 2019

In order to enhance combustion efficiency and reduce atmosphere pollutants, it is essential to measure carbon monoxide (CO) concentration precisely in combustion exhaust. CO is the important gas species regarding pollutant emission and incomplete combustion because it can trade off with NOx and increase rapidly when incomplete combustion occurs. In the case of a steel annealing system, CO is generated intentionally to maintain the deoxidation atmosphere. However, it is difficult to measure the CO concentration in a combustion environment in real-time, because of unsteady combustion reactions and harsh environment. Tunable Diode Laser Absorption Spectroscopy (TDLAS), which is an optical measurement method, is highly attractive for measuring the concentration of certain gas species, temperature, velocity, and pressure in a combustion environment. TDLAS has several advantages such as sensitive, non-invasive, and fast response, and in-situ measurement capability. In this study, a combustion system is designed to control the equivalence ratio. Also, the combustion exhaust gases are produced in a Liquefied Petroleum Gas (LPG)/air flame. Measurement of CO concentration according to the change of equivalence ratio is confirmed through TDLAS method and compared with the simulation based on Voigt function. In order to measure the CO concentration without interference from other combustion products, a near-infrared laser at 4300.6 cm^-1 was selected.

• Journal of the Korean Society of Combustion
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• v.19 no.3
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• pp.8-17
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• 2014

The aims of this research were to evaluate effects of biomass co-firing to pulverized coal power plants and the variation of co-firing ratios on the plant efficiency related to power consumption of auxiliary system and flue gas characteristics such as production and component by process simulation based on the existing pulverized coal power plant. In this study, four kinds of biomass are selected as renewable fuel candidates for co-firing: wood pellet(WP), palm kernel shell(PKS), empty fruit bunch(EFB) and walnut shell(WS). Process simulation for various biomass fuels and co-firing ratios was performed using a commercial software. Gas side including combustion system and flue gas treatment system was considering with combination of water and steam side which contains turbines, condenser, feed water heaters and pumps. As a result, walnut shell might be the most suitable as co-firing fuel among four biomass since when 10% of walnut shell was co-fired with 90% of coal on thermal basis, flue gas production and power consumption of auxiliary systems were the smallest than those of other biomass co-firing while net plant efficiency was relatively higher than those of other biomass co-firing. However, with increasing walnut shell co-firing ratios, boiler efficiency and net plant efficiency were expected to decrease rather than coal combustion without biomass co-firing.

• Journal of the Korean Society of Combustion
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• v.21 no.4
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• pp.39-47
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• 2016

The aims of this research were to investigate combustion characteristics of lab-scale pressurized oxy-fuel combustion(POFC) system. In this study, the reactor, 800 mm long, was equipped with co-axial burner. Low calorific value syngas that is composed of mainly CO and $H_2$ was used as fuel whereas pure oxygen was used as an oxidant. Thermal heat input to the reactor varied from 2.6 kW to 6.1 kW. The reactor pressure also increases from atmospheric up to 15 bar. The results show that as the pressure increase, the temperature of reactor decreases on the whole in all cases. A significant temperature drop was observed especially at the bottom section of the reactor that exist flame. In addition, the flame instability increases as the pressure increases. Furthermore $NO_x$ emissions increases from atmospheric up to 2 bar. However beyond 2 bar, $NO_x$ emission reduces as pressure increases. Lastly $NO_2$ ratio in $NO_x$ also increases as pressure increases.

• Journal of the Korean Society of Combustion
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• v.20 no.3
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• pp.21-26
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• 2015

This study was performed to provide the information of the combustion characteristics of n-butanol fuel in accordance with the n-heptane fuel mixing ratio. The closed homogeneous reactor model was used for the analysis. The analysis conditions were set to 800 K of the initial temperature, 20 atm of initial pressure and 1.0 of equivalence ratio. The results of analysis were compared in terms of combustion temperature, combustion pressure, CO, Soot and $NO_X$ emissions. The results of combustion and exhaust emission characteristics showed that ignition delay was decreased and the combustion temperature was increased as the n-heptane mixing ratio was increased. Also, the carbon monoxide(CO) was slightly decreased however, the soot and nitrogen oxides($NO_X$) increased a little in accordance with the n-heptane fuel mixing ratio. In addition, the pressure difference was almost the same in any conditions.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.215.2-215.2
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• 2010

지구온난화의 주범으로 알려진 $CO_2$의 대기 중 농도는 산업혁명 이전 280ppm에서 산업 혁명 이후 375ppm으로 증가하였다. 정부 간 기후변화패널(IPCC)의 기후변화 시나리오에 의하면, 지금부터 다양한 감축노력을 한다 할지라도 $CO_2$ 증가추세는 계속되어 2100년경에는 대기 중 $CO_2$농도가 600~950ppm에 이를 것으로 예측하고 있다. 현재까지 화력발전부분은 온실가스($CO_2$)의 최대 배출 원으로 알려져 있으며 이 분야의 $CO_2$ 회수기술은 연소 후 포집(Post-combustion), 순산소 연소(Oxy-fuel combustion), 연소 전 탈탄소화(Pre-combustion) 3가지로 크게 구분된다. 이중 석탄가스화복합발전(IGCC)기술과 연계하여 $CO_2$를 회수할 수 있는 방법이 연소 전 탈탄소화 기술이다. 핵심기술은 $CO_2$ 분리공정으로 적용 될 수 있는 기술로서는 흡착 흡수법, 막분리법 그리고 가스 하이드레이트가 있으나 아직까지 우리나라의 가스 하이드레이트 기술은 전무한 형편이다. 본 연구에서는 가스 하이드레이트 형성원리를 이용하여 정온 정압 조건에서 $CO_2/H_2$ 하이드레이트를 제조하였으며 특히, 하이드레이트 형성 촉진제인 TBAB(Tetra-n-butyl ammonium bromide)를 첨가하여 TBAB 농도에 따른 상평형 및 속도론 실험을 수행 하였다. 또한 라만 분석을 통하여 $CO_2$ 회수 분리에 대한 연구도 병행하였다.