• Journal of Energy Engineering
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• v.22 no.2
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• pp.169-174
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• 2013

An experimental study has been conducted for the design of the regenerative oxy-fuel combustion system with ceramic ball. Various design parameters are considered such as ball size, regenerator weight, and combustion load. Regenerative system with a pair of oxygen burners and regenerators is set up and the temperature of oxygen and exhaust gas passing through ball regenerator is measured. It is shown that the temperature distributions with time are affected by ball diameter and regenerator weight, and the significant temperature change is observed by combustion load. As the ball size decreases and the regenerator weight increases, the regenerating temperature efficiency increases. It is found that the heat recovery ratio is low despites of high regeneration temperature efficiency.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.8
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• pp.639-648
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• 2013

This paper describes on the NOx/CO emission characteristics, temperature characteristics and flame structures when firing coal derived synthetic gas especially for gases of Buggenum and Taean IGCC. These combustion characteristics were observed by conducting ambient-pressure elevated-temperature combustion tests in GE7EA model combustor when varying heat input and nitrogen dilution ratio. Nitrogen addition caused decrement in adiabatic flame temperature, thus resulting in the NOx reduction. At low heat input condition, nitrogen dilution raised the CO emission dramatically due to incomplete combustion. These NOx reduction and CO arising phenomena were observed at certain flame temperature of $1500^{\circ}C$ and $1250^{\circ}C$, respectively. As increasing nitrogen dilution, adiabatic flame temperature and combustor liner temperature were decreased and singular points were detected due to change in flame structure such as flame lifting. From the results, the effect of nitrogen dilution on the NOx/CO and flame structure was examined, and the test data will be utilized as a reference to achieve optimal operating condition of the Taean IGCC demonstration plant.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.460-466
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• 2009

식용유 화재는 일반유류와는 달리 연소형태나 소화작업에 있어 큰 차이를 보이고 있다. 최근 5년간 특수화재 가운데 원인별 화재 통계를 보면 식용유 화재의 발생빈도는 점점 증가하고 있지만, 식용유에 대한 화재 위험성에 관한 연구는 거의 전무한 실정이다. 본 연구에서는 식용유의 연소특성 알아보기 위하여 종류별 인화점, 연소점, 발연점에 대하여 클리블랜드 인화점 시험기를 사용하여 측정하였고, 최소자연발화온도 및 발화 비발화 영역 비교를 통한 발화한계 온도 곡선을 도출하였으며, 자연발화온도와 발화지연시간과의 관계를 측정하였다. 이 결과를 통하여 식용유의 화재 위험성 평가에 대한 기초적인 자료로써 제시할 수 있었다.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.6
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• pp.20-29
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• 2013

Turbulent flow and combustion characteristics in a micro can combustor with a baffle plate are investigated by a Reynolds Stress Model. In order to examine the geometric effects on the turbulent combusting flow, several baffle configurations are selected. The interrelation between the flow structure and the thermal field are investigated by examing the variation of recirculation region, flame length and heat loss. For the flow mixing, the decreasing air hole is more efficient than the decrease of the fuel hole. As the fuel or air hole diameter decreases, combustion efficiency is enhanced and flame length is decreased. Additionally, as the diameter of air hole decreases, the heat loss and combustion temperature are increased, while they are reduced with decreasing the diameter of fuel hole.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1997.04a
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• pp.205-211
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• 1997

최근 유도무기 분야에서 많이 사용되고 있는 가스발생기는 온도가 낮고, 독성이나 부식성이 없는 연소 가스를 요구하고 있기 때문에 산화제로 Ammonium Nitrate(AN)를 주로 사용하고 있다. 그러나 순수한 AN은 온도에 따라 상이 변하는 단점이 있기 때문에 Phase Stabilized Ammonium Nitrate(PSAN)을 사용하고 있으며, 일반적으로 PSAN은 AN과는 다른 연소특성을 갖는다. 본 연구에서는 가스발생기용 추진제의 조성을 연구하면서, 상안정제로 $KNO_3$와 $KCIO_4$을 사용하여 자체적으로 제조한 PSAN들과 ZnO=3%인 PSAN을 사용하여 얻은 추진제의 연소특성을 고찰하였고, 연소촉매를 사용하거나 RDX나 소량의 AP를 사용하여 보다 다양한 연소속도를 갖는 추진제를 제조할 수 있었다.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.230-231
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• 2000

최근 자동차, 항공기 등 연소과정을 수반하는 산업이 발전함에 따라 연소환경에 대한 관심이 높아지고 있다. 그런데 연소환경을 접촉식 방법으로 측정하게 되면, 측정기기가 연소환경에 영향을 주기 때문에 정확한 측정을 하기는 어렵다. 그래서 레이저를 이용한 비접촉식방법이 활용되고 있으며,$^{(1)}$ 그 중에서 LIGS(laser induced grating spectrosopy)나 DFWM(degenerate four wave mixing)$^{(1)}$ 은 신호대 잡음비가 높기 때문에 미세량으로 존재하는 분자를 검출하는데 유용할 뿐만 아니라 2차원 영상수집도 가능하다. 또한 LIGS의 시분해 신호를 분석하면 연소장내의 온도와 입자의 밀도 등을 산출할 수 있다. 본 실험에서는 대기압에서 불완전 연소장의 soot에 대한 신호를 수집, 분석하여 화염 위치에 따른 온도 변화와 soot의 농도 등을 정량적으로 조사했다.$^{(2)}$ (중략)

• Journal of Energy Engineering
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• v.12 no.4
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• pp.267-273
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• 2003

Emulsion fuel is a very attractive fuel because of its energy saving and pollution prevention properties. We investigated and compared the combustion efficiency of B-C oil and emulsion fuel i.e. fuel made from the mixture of B-C oil and waste water. By installing an R-type thermocouple and an optical pyrometer on each side of the boiler, and by placing a combustion analyzer at the point of gas emissions, We were able to measure and compare each flame temperature, combustion rate and the concentration of emitted gas when B-C oil and emulsion fuel are burned. The following results were obtained: The flame temperature of emulsion fuel at the front and rear of the boiler is about 50$^{\circ}C$ lower than the flame temperature of B-C oil. The reason for this difference in temperature is that both latent and sensible heat is lost due to the moisture in the waste water of emulsion fuel. An analysis of emitted gases shows that when emulsion fuel is used polluting substances decrease also the concentration of CO becomes considerably lower. The combustion efficiency for B-C oil and emulsion fuel is 85.5% and 84.8% respectively.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.5
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• pp.552-559
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• 2008

Three dimensional numerical analysis were performed to investigate the combustion characteristics in a tangentially fired pulverized coal boiler. The predicted values at the outlet of economizer for the gas temperature, O$_2$, NO, CO were been compared with the measured data. By using the actual operating conditions of the power plant, the distribution of velocity, gas temperature, O$_2$, CO, CO$_2$ and NO as well as the particle tracking in the boiler were investigated. Throughout the present study, the non-uniform distribution of flue gas temperature in front of the final superheater might be resulted from the residual swirl flow in the upper furnace of the boiler. The present analysis on non-uniform distribution of the gas temperature could provide the useful information to prevent the frequent tube failure from happening in the final superheater of the tangentially coal-fired boiler.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.81-90
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• 2004

This paper describes the results of combustion performance test of fuel-rich gas generator(GG) using LOx and kerosene as propellant at off-design conditions. The chamber pressure is thought to be a function of O/F ratio and total propellant mass flow rate. The test shows that the spatial temperature deviation at the exit of gas generator remains within 7.5K and that the average gas temperature at the exit is a function of propellant O/F ratio. The results of firing test of gas generator at off-design conditions, especially the relation between gas temperature and O/F ratio, can provide useful data for the design of future gas generator and for the development of low-O/F ratio reaction analysis code.

• Fire Science and Engineering
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• v.21 no.4
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• pp.25-31
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• 2007

The combustion characteristics and combustion heat of sandwich panel cores were analysed using variable external irradiation level. The characteristics such as ignition time, critical heat flux, ignition temperature and surface temperature profile were measured. Fuel samples were exposed to incident heat fluxes from 15 to $50\;kW/m^2$. For the measurement of various combustion characteristics, the size of specimen was $100\;mm\;{\times}\;100\;mm\;{\times}\;50\;mm$ and the samples were 3 different kinds. As results, Type B showed the best characteristics in measurement of combustion heat and ignition temperature and Type C showd the best characteristics in critical heat flux and surface temperature profile than that of the other two. In conclusion, we knew that Type C had the best performance in fire safety from all data of this study.