• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.97-100
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• 2014

The combustion and emission characteristics of propane and n-butane which are the main components of LPG were compared with gasoline. The experiment was performed in a stratified DISI engine under lean combustion conditions. Mixtures of propane and n-butane wre more homogeneous because propane and n-butane have better evaporation characteristics. As a result, combustion speeds of n-butane and propane were slower, and emission levels of NOx and PM were lower. However, in spite of better evaporation, PM from propane was higher.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 춘계학술대회논문집
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• pp.329-334
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• 2009

An oxy-fuel boiler has been developed to capture $CO_2$ from the exhaust gas. FGR (flue gas recirculation) is adopted to be compliant with the retrofit scenario. Numerical simulations have been performed to study the detailed physics inside the combustion chamber of the boiler. The temperature field obtained from the simulation agrees with the flame image from the experiment. The FGR combustion yields similar heat transfer characteristics with the conventional air combustion while the flame is formed further downstream in case of the FGR combustion.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.859-864
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• 2000

This paper reports a numerical flow characteristic analysis in gas boiler combustion chamber. The numerical results with simplification and assumptions were found within 30% of the experiment. A lot of geometrical modification has been invested in attempt to obtain the uniform flow in the combustion chamber exit. As a result, the velocity magnitude of the combustion chamber is relate with the hole size in air distribution plate. The velocity uniformity of the combustion chamber is relate with the number of holes and location in air distribution plate.

• 한국자동차공학회논문집
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• 제4권3호
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• pp.220-231
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• 1996

In this research, we use IDI type constant volume combustion chamber which may make up stratified combustion to construct the design back data of lean-burn engine. Some experiments are conducted by the passagehole angle in the adapter of main chamber and sub-chamber. The effects on the combustion characteristics according to the ignition timing are investigated. The used fuel is methanol prospective for alternative fuel. Fuel is injected under 10.78MPa using solenoid and accumulator. As the results of the experiment, combustion characteristics reveals that ignition timing, passagehole angle and shape greatly effects on. Lean inflammability limit is extended to 0.45 in equivalence ratio.

• 항공우주시스템공학회지
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• 제3권4호
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• pp.41-49
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• 2009

This paper present result of numerical simulation of premixed combustion around a triangle Bluff Body. And a numerical simulation of a premixed flame stabilization by a bluff body was performed using LES Model. The calculated results from the LES showed a good agreement with experiment data than k-model. Premixture combustion has flammability limit, quenching distance, smallest ignition energy has the combustion quality of the back. Bluff body makes a recirculation zone. Therefor velocity of behind bluff body is very slow. It was caused by slowly position speed and the fire occurred after the Bluff Body. Occurrence of fire it made the waste gas of high speed and the thrust made well.

• Journal of Acupuncture Research
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• 제17권1호
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• pp.89-105
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• 2000

In order to obtain the clinical data on the different effects of the three different methods of indirect moxibustion, moxa-combustion time, peak temperature, average temperature, maximum gradient temperature, average gradient temperature, and moxa-combustion calorie rate of the input period in ARIRANG, JANG, PUNG were measured through this experiment. The results of the experiment were as follows : 1. In the combustion time, during the input period ARIRANG had the longest combustion time followed by PUNG, JANG in a descending order but these were not acknowledged to have significant difference each other. 2. In the peak temperature of the input period, PUNG had the highest temperature followed by ARIRANG, JANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 3. In the average temperature, during the input period, PUNG had the highest temperature followed by JANG, ARIRANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 4. In the maximum gradient temperature, during the input period, PUNG had the highest temperature followed by ARIRANG, JANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 5. In the average gradient temperature, during the input period, PUNG had the highest temperature followed by ARIRANG, JANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 6. In the moxa-combustion calorie rate, during the input period, JANG had the highest temperature followed by ARIRANG, PUNG in a descending order. ARIRANG and PUNG were acknowledged to have significant difference with JANG. ARIRANG and PUNG however were not acknowledged to have difference each other.

• Journal of Acupuncture Research
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• 제17권1호
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• pp.75-88
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• 2000

In order to obtain the clinical data on the different effects of the three different methods of indirect moxibustion, moxa-combustion time, peak temperature, average temperature, maximum gradient temperature, average gradient temperature, and moxa-combustion calorie rate of the retaining period in ARIRANG, JANG, PUNG were measured through this experiment. The results of the experiment were as follows : 1. In the combustion time, during the retaining period ARIRANG had the longest combustion time followed by PUNG, JANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 2. In the average temperature, during the retaining period, PUNG had the highest temperature followed by JANG, ARIRANG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 3. In the maximum gradient temperature, during the retaining period, PUNG had the highest temperature followed by JANG, ARIRANG in a descending order. JANG and PUNG were acknowledged to have significant difference with ARIRANG. JANG and PUNG however were not acknowledged to have difference each other. 4. In the average gradient temperature, during the retaining period, JANG had the highest temperature followed by ARIRANG, PUNG in a descending order. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other. 5. In the moxa-combustion calorie rate, during the retaining period, PUNG had the highest temperature, ARIRANG, JANG were founded in error limits. ARIRANG and JANG were acknowledged to have significant difference with PUNG. ARIRANG and JANG however were not acknowledged to have difference each other.

• 한국화재소방학회논문지
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• 제24권1호
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• pp.1-7
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• 2010

본 연구에서는 지표화의 대표적인 연소물질인 굴참나무(Quercus Variabilis: Q.V.)와 소나무(Pinus Densiflora: P.D.) 낙엽을 이용하여 연료의 밀도 변화에 따른 열 유체속도, 연소온도, 질량감소속도, 화염높이 및 연소시간 등의 연소특성을 분석하였다. 바스켓 높이는 10cm, 지름 20, 30, 40 그리고 50cm의 원통형 바스켓에 밀도별로 각각 채운 후 표면에 점화원을 인가하여 실험을 실시하였다. 침엽수종 낙엽의 경우 밀도와 지름의 증가함에 따라 질량감소속도, 화염지속시간, 화염의 높이 그리고 연소시간은 증가한 반면, 활엽수종 낙엽의 경우 질량감소속도와 화염높이는 증가하다가 감소하였으며 화염지속시간과 연소시간은 증가하였다. 또한, 기체유속 및 온도는 화염 높이가 커질수록 증가하는 경향을 나타내었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.157-159
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• 2014

This article describes an investigation of basic combustion characteristics of radiant burner with various firing rate and equivalence ratios in porous metal. As a main experimental condition, firing rates and equivalence ratios each were adjusted from 204 to $408kW/m^2$ and 0.6 to 1.3. The purpose of this study is to investigate radiation efficiency using two experiment methods. The first way is to calculate the radiation efficiency by measuring the temperature of the burner surface, and the second is to compute the radiation efficiency by measuring the radiation intensity of the burner surface with a radio meter. The value of the radiation efficiency did not exactly match in the two cases. But we figured out that in accordance with increasing heat power, radiation efficiency was decreased. And additional complementary experiment on the relationship between these values is needed.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.127-132
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• 2001

A numerical study was carried out to investigate the combustion phenomena in a model Scramjet engine, which had been experimentally studied in the University of Tokyo using a high-enthalpy supersonic wind tunnel. The main airflow was 2.0 in Mach number and the total temperature of hot flow was 1800K. Equivalence ratio was set to be rather higher value of 0.26 than that of experiment to investigate the effect of strong precombustion shock. The results showed that self-ignition occurred at the rear bottom wall of the combustor and combined with the shear layer flame between fuel jet and main airflow. Then, precombustion shock was generated at the step location and reversely enhanced the mixing and combustion process behind the shock. Due to the high equivalence ratio, the precombustion shock moved upstream of the step compared with that of experiment.