• 대한기계학회논문집
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• 제13권3호
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• pp.508-516
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• 1989

본 연구는 석탄의 맥동연소과정을 비맥동연소와 빅교실험을 하여 연소특성 을 가시적으로 관찰하고 연소율 등의 연소특성을 구하며 고체연료의 맥동연소과정을 밝히고 맥동연소기 개발의 기초자료를 얻는데 목적을 두었다.

• 한국연소학회지
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• 제17권4호
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• pp.60-65
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• 2012

The MILD combustion and pollutant emission characteristics were investigated computationally. The temperature of supplying air-stream and mixing rate (${\Omega}$) of exhaust gas in the air-stream were adjusted to investigate the effects of those parameters on the MILD combustion in jet flow field. The emission indices for NO (EINO) and CO (EICO) were introduced to quantify the amount of those species emitted from the combustion. The high-temperature region disappeared gradually as the mixing rate increased for fixed air-stream temperature. The EINO increased as the air-stream temperature became higher for fixed mixing rate, and the EINO decreased dramatically with increasing the mixing rate for each air-stream temperature condition. The EICO also decreased with increasing the mixing rate and it was nearly independent of air-stream temperature except for near ${\Omega}$ = 0.7. It was found that the CO supplied in the air-stream can be destroyed in the MILD combustion over the certain mixing rate.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1999년도 제19회 KOSCO SYMPOSIUM 논문집
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• pp.129-138
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• 1999

In this paper, our main issue is that establishing the control procedure of continuous gas flow rate according to combustion fan RPM. For this, first, we decide the optimum operating condition of gas swirl burner through analysis of combustion characteristics - thermal efficiency, combustion efficiency and exhaust gases such as CO, $CO_{2}$, $O_{2}$, $NO_{x}$ and THC. Second, fuel gas flow rate of gas valve is decided with considering excess air ratio and combustion fan RPM is decided by the target of combustion air flow rate. Finally, experimental operating equation is acquired by regression for gas valve and combustion fan. This equation is the control equation of continuous gas flow rate and always gas flow rate is decided by combustion fan operating RPM.

• 한국분무공학회지
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• 제1권3호
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• pp.29-36
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• 1996

The present study systematically investigates the effect of evaporation rate on the combustion characteristics and the flame stabilization in a gasoline engine. A constant volume combustion chamber was used to elucidate a basic combustion characteristics and the premixer was installed to control temperature and equivalence ratio. And the maximum pressure, combustion duration and flame propagation according to the evaporation rate were measured to determine the optimal temperature range for evaparating a gasoline fuel. These experimental results indicate that the combustion characteristics such as combustion chamber pressure and combustion duration were deteriorated by decreasing surrounding temperature of fuel injected. It was also found that the overall gasification process for gasoline fuel was strongly influenced by a combustion chamber temperature rather than a premixer temperature.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.301-303
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• 2014

Flameless combustion, well known as MILD (Moderate Intensity Low oxygen Dilution) combustion or CDC(Colorless Distributed Combustion), is considered as one of the promising technology for achieving low NOx and CO emissions with improving thermal efficiency of combustion system. In this paper, the effects of exhaust gas dilution rate on formation of flameless combustion of liquid fuel were analyzed using three-dimensional numerical simulations for application of gas turbine combustor with high power density. Results show that the local high temperature region was decreased and flame temperature was spatially uniformly distributed due to higher dilution rate of burnt gas as similar pattern of gas phase flameless combustion. But the evaporation and mixing process of liquid fuel are found to be another important factors for formation of flameless combustion.

• 한국분무공학회지
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• 제2권2호
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• pp.24-34
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• 1997

This paper describes the investigation of combustion characteristics of gasoline-methanol blend in constant volume combustion chamber. A constant volume combustion chamber was used to elucidate a basic combustion characteristics and the premixer was installed to control temperature and equivalence ratio. And the maximum pressure, combustion duration and flame propagation according to the evaporation rate were measured to determine the optimal temperature range for evaporating a blend fuel. These experimental results indicate that the combustion characteristics such as combustion chamber pressure and combustion were deteriorated by decreasing surrounding temperature of fuel. These experimental results indicate that the combustion characteristics such as combustion chamber pressure and combustion were deter orated by decreasing surrounding temperature of fuel injected. It was also found that the overall gasification process for methanol blend fuel was influenced by a combustion chamber temperature rather than a premixer temperature.

• 열처리공학회지
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• 제8권2호
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• pp.120-126
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• 1995

The effects of heating rate on the combustion temperature, the ignition temperature, the microstrurcture and the shape memory ability of products formed by combustion were investigated. The ignition temperature decreased with increasing heating rate. Combustion temperature and ${\Delta}T$(difference temperature between the ignition temperature and the combustion temperature) increased with increasing heating rate. The grain size of the product increased with increasing heating rate. Combustion synthesis did not completely occur below the heating rate of $10^{\circ}C/min$. NiTi intermetallic compound was completely formed at the heating rate of $600^{\circ}C/min$ and the product by combustion method had a good shape memory effect.

• 한국안전학회지
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• 제15권3호
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• pp.83-87
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• 2000

Combustion characteristics of immobilized benzene and toluene in sands were studied. Experiments were performed by burning benzene and toluene immobilized on sands(particle size 0.1~0.5mm) to measure combustion rate and combustion temperature. The longer time from ignition to extinguishment was resulted from the larger particle size exhibited the higher mass burning rate. Of aromatic compounds tested the relative magnitude of facilitation of combustion was benzene and toluene. Combustion temperature of benzene and toluene without regard to the types of benzene and toluene was not increased with smaller sand. However, with larger sands, combustion temperature of benzene and toluene were increased by 50~$100^{\circ}C$ and the highest combustion temperature was obtained with larger sands.

• 대한기계학회논문집B
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• 제26권10호
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• pp.1387-1393
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• 2002

The measurement of velocity and stain rate field has been conducted in opposed impinging jet combustion. When a smaller diameter (5mm) orifice of pre-chamber was used, previous studies had reported that the combustion phase showed a shift from weak turbulent combustion to moderate turbulent combustion in the modified Borghi Diagram. In the case with smaller orifice diameter (5mm), NOx emission was substantially reduced by a factor 1/2 while the combustion pressure remains at the same as that in the conventional combustion. Hence, in this study, the experiment setup using PIV technique was designed to identify the relation of the strain rate distribution and NOx reduction associated with moderate turbulent combustion. As a result, it was found that the highly strained pockets are widely distributed during the combustion in the middle of chamber when the orifice diameter is 5mm. And the corresponding PDF distribution of strain rates she was the smoothly distributed strain .ate within the range of ｜$\pm$1000｜ (1/sec) rather than a spike shape about zero point. This is the unique feature observed in the combustion with 5mm orifice diameter. Therefore, it can be concluded that the substantial NOx reduction in opposed impinging combustor is mainly attributed to the strain rate distribution within the range of ｜$\pm$1000｜resulting in the combustion phase shift to moderate turbulent combustion.

• 한국자동차공학회논문집
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• 제3권3호
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• pp.129-139
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• 1995

This study investigates the combustion characteristics of methane-hydrogen-air premixture in a constant volume combustion chamber. Primary factors of the combustion characteristics of methane- hydrogen-air premixture are the equivalence ratio and hydrogen supplement rate. In the case of $\phi$= 1.1, maximum combustion pressure and heat release rate have peaks, and they increase as the initial pressure and hydrogen supplement rate increase. The total burning time is also the shortest at the $\phi$= 1.1, it shorten by lowering the initial pressure and by increasing the hydrogen supplement rate. The maximum flame temperature is shown at the $\phi$= 1.0, and increasing the initial pressure and hydrogen supplement rate, it increases. The concentration of NO reveals the highest value at the $\phi$= 0.9, and it increases by increasing the initial pressure and hydrogen supplement rate. It is also found that the limit of lean inflammability of methane-hydrogen-air premixture is greatly widened by increasing the hydrogen supplement rate.