• 한국분무공학회지
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• 제14권2호
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• pp.84-89
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• 2009

In this research, combustion and spray characteristics were investigated experimentally in a constant volume chamber by applying different composition rates of octane number in diesel fuel to a common-rail system. For the visualization, the experiment was carried out under different injection pressures and different cetane number. The test was done by three different types of diesel fuels, the different composition rates of cetane number in diesel fuel and HBD. In summary, this research aims to investigate the combustion characteristics in the application of fuels and compare the results with performance of conventional diesel fuel. This experimental data may provide with fundamentals of the development of diesel engines in future.

• 오토저널
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• 제10권3호
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• pp.45-50
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• 1988

The measurement system of the pressure in engine cylinder is developed with the aids of the microcomputer, A/D converter and simple electrical circuits. The experiment is performed in 4 cycle single cylinder Gasoline engine. When data for the pressure progress is sampled, clock signal or signal from the crank angle is used as trigger. The variation of the pressure during the cycles can be well obtained experimentally. So, the informations which are necessary in the combustion analysis, i.e. expansion pressure, indicated mean effective pressure, the magnitude and time of the maximum pressure ignition time, the rate of pressure rise and heat release and combustion rates can be obtained by the calculation using experimental data. Also, the informations about the after-burning process, the existence of the detonation waves and end time of combustion can be investigated from this study.

• 한국자동차공학회논문집
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• 제10권2호
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• pp.31-39
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• 2002

Recently, many researches have been performed to improve the performance of the combustion and emission in a D.I.Diesel engine. One of the main factors effect on the characteristics of combustion is the characteristic of air-fuel mixing. Thus, swirl flow has been used widely to improve the air-fuel mixing in a D.I.Diesel engine. Since this swirl flow has interaction with other factors, in this study, the characteristics of the combustion and the flame effected by the swirl flow generated by SCV was investigated. From this experiment, the interactions of the swirl flow and the injection timing made clear. In addition, the effects of swirl and injection timing on the diffusion flame were clarified.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1019-1024
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• 2008

A 3 MW class oxy-fuel boiler has been developed to capture $CO_2$ from the exhaust gas. The system is a scale-up of the previous 0.5 MW class system in general. A heat exchanger and a mixer are additionally installed to stabilize the flame for the FGR mode. The system yields the exhaust gas with $CO_2$ concentration over 90% and reduced NO emission to 1/10 of conventional air combustion system.

• 한국연소학회지
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• 제6권1호
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• pp.14-19
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• 2001

Interests and importance of down-scale combustor is increasing with the emerging need for miniaturized power source which is now a bottleneck of micro system development. But in down scaled combustor increased heat loss compared to thermal energy generation inhibits the usability and application of the device, so as a preliminary work of down scaled combustor fabrication. Modeling tool for the device should be established, in this study modeling approach of closed vessel combustion phenomena that can express heat loss effect and resulting quenching is proposed and the result is compared with experiment data. From this model heat loss effect following combustor scale down can be further understood, and further more design parameter and analysis tool can be obtained.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1321-1335
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• 2022

This study was conducted to investigate the effect of absorption coefficient models on the P1 radiation model for a premixed hydrogen flame containing the water vapor. A CFD combustion simulation analysis was performed using XiFoam, one of the open-source CFD solvers in OpenFOAM. The solver using the flamelet combustion model has been modified to implement radiative heat transfer. The absorption coefficient models used in this study the grey-mean model and constant model, and for comparison, case without radiation was added. This CFD simulation study consisted of benchmarking the THAI HD-15 and HD-22 experiments. The difference between the two tests is the inclusion of water vapor in the condition before ignition. In the case of the HD-22 experiment containing water vapor in the initial condition, the simulation results show that the grey-mean absorption coefficient model has a strong influence on the temperature decrease of the flame and on the change in pressure inside the vessel.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.77-78
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• 2023

This paper experimentally examined the recycling of combustion by-products emitted from a combined heat and power plant using lignocellulosic biomass fuel. Physical and chemical analyzes were performed on Bio-SRF and three types of wood pellet combustion by-product samples (fly-ash, FA). As a result of the experiment, the compressive strength of mortar substituted with 5, 10, and 20% of FA compared to the cement weight was found to be excellent, and its recyclability was confirmed as a substitute for existing admixtures.

• 한국가스학회지
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• 제16권6호
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• pp.7-16
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• 2012

화재시 당면할 수 있는 위험성의 여러 인자 가운데 연소 독성 영향은 피난 및 최종 생존에 중요한 영향을 미치고 있다. 화재 독성에 지금까지 대한 대부분의 연구는 치사 측면에 국한되어 왔다. 이에 본 연구에서는 대표적인 질식성 가스인 HCN을 대상으로 가스유해성시험방법(KS F 2271)을 통하여 실험동물(흰쥐)에 직접 독성가스를 흡입시킨 후 평균행동정지시간을 측정하고, 이들 실험동물군의 내부 장기 변화, 혈액학 분석 및 단세포전기영동분석을 통해 연소 독성가스가 생체에 미치는 영향을 정량적으로 분석하고자 하였으며, 기존 가스유해성시험에서 확인할 수 없었던 접근(병리검사, 혈액검사, 혈액생화학검사, 단세포전기영동분석)을 통해 연소 독성학 분야의 생물학적 위험도를 측정하고자 하였다.

• 대한한의학회지
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• 제15권2호
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• pp.241-252
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• 1994

It is known that the pattern of combustion temperature can be classified into preheating, heating. retaining and cooling periods. In this experiment. the authors have studied the heating mechanism by the density of moxa material during the heating and retaining periods. The starting point. the point at which it begins to reach the maximum gradient temperature. the ending point of the heating period. and the ending point of the retaining period were measured in order to get effective stmulation by repetition of moxa-combustion. For the experiment. samples of 300mg. 400mg, and 500mg of moxa material were molded into conical molds with each 10mm in diameter and height resulting in the volume of $0.26cm^3$. The following results were obtained: The $300mg/0.26cm^3$ denstiy sample reached al1 points tested faster than the samples of $400mg/0.26cm^3$ and $500mg/0.26cm^3$ It dose not reveal any statistical differences between $400mg/0.26cm^3$ and $500mg/0.26cm^3$ in the ending point. the point at which it begins to reach the maximum gradient temperature of the heating period or the ending point of the reataining period The only difference shown was in the starting point of the heating period. According to the above results. it is concluded that the lower density moxa material reached each point of the the respective period faster than the high density moxa material.

• 동력기계공학회지
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• 제15권5호
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• pp.10-15
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• 2011

This paper describes the engine performance and combustion characteristics of a CRDI diesel engine, operated by electronically controlled diesel fuel injector with variable injection timing. This experiment focused on fuel injection timing and pressure about combustion characteristics of CRDI diesel engine. EGR was excepted because it would be furtherly analyzed with additional experiments. The experiment was conducted under the circumstance of engine torque for 4, 8, 12 and 16 kgf-m and fuel injection timing for $15^{\circ}$, $10^{\circ}$ and $5^{\circ}$ BTDC, at the engine speed of 1100, 1400, 1700 and 2000 rpm. Fuel injection was controlled to retard or advance initiation of the injection event by electronically controlled fuel injection unit injector on the personal computer. When fuel was injected into the cylinders of a CRDI diesel engine it would go through ignition delay before starting of combustion. Therefore, fuel injection timing of CRDI diesel engine had a significant effect upon performance and combustion characteristics. Depending on the injection timing the fuel consumption rate following the rotational speed and torque was 3~78 g/psh (1.7~30.6%). The range of fuel injection timing that resulted in low fuel consumption overall was BTDC 15-10 degrees.