• Journal of the Korean Society of Industry Convergence
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• v.4 no.4
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• pp.403-411
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• 2001

A criterion for evaluation of burners has changed recently, and the environmental problems are raised as a global issue. Burners with higher thermal efficiency and lower oxygen in the exhaust gas, evaluated better. To comply with environmental regulations, burners must satisfy the $NO_x$ and CO regulation. Consequently. 'good burner' means one whose thermal efficiency is high under the constraint of $NO_x$ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop a feedback control scheme whose output is the consistency of $NO_x$ and CO. This paper describes the development of a real time flame diagnosis technique that evaluate and diagnose the combustion states, such as consistency of components in exhaust gas, stability of flame in the quantitative sense. In this paper, it was proposed on the flame diagnosis technique of burner using Neuro- Fuzzy algorithm. This study focuses on the relation of the color of the flame and the state of combustion. Neuro- Fuzzy learning algorithm is used in obtaining the fuzzy membership function and rules. Using the constructed inference algorithm, the amount of $NO_x$ and CO of the combustion gas was successfully inferred.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.10 no.1
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• pp.76-82
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• 2005

This paper presents the combustion characteristics of hydrocarbon fuel from a conventional pressureswirl nozzle of a small-scale burner. The nozzle has orifice diameters of 0.256 mm and liquid flow rates raging from 50 to 64 mL/min were selected for the experiments. The furnace temperature distribution along the axial distance, the gas emission such as CO, $CO_2,\;NOx,\;S0_2,$ flue gas temperature, and combustion efficiency were studied. The local furnace and flue gas temperatures decreased with an increase in air velocity. At injection pressures of 1.1 and 1.3 MPa the maximum furnace temperatures occurred closer to the burner exit, at an axial distance of 242 mm from the diffuser tip. The CO and $CO_2$ concentrations decreased with an increase in air velocity, but they increased with an increase in injection pressure. The effect of air velocity on NOx was not clearly seen at low injection pressures, but at injection pressure of 1.3 MPa it decreased with an increase in air velocity. The effect of air velocity $SO_2$ concentration level is not well understood. The combustion efficiency decreased with an increase in air velocity but it increased with an increase in injection pressure. It is recommended that injection pressure less than 0.9 MPa with air velocity not above 8.0 m/s would be suitable for this burner.

• Journal of the Korean Society of Combustion
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• v.17 no.4
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• pp.5-10
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• 2012

The reformer system is a chemical device that drives the conversion of hydrocarbon to hydrogen rich gas under high temperature environment($600-1,000^{\circ}C$). Generally, NG(Natural Gas) or AOG(Anode Off Gas) is used as fuel of fuel cell reformer combustion system. The experimental study to analyze the combustion characteristics of a premixed ceramic burner used for 0.5-1.0 kW fuel cell reformer was performed. Ceramic burner experiments using NG and AOG were carried out to investigate the flame stability characteristics by heating capacity, equivalence ratio and different fuels respectively. The results show that surface flames can be classified into green, red, blue and lift-off flames as the equivalence ratio of methane-air mixture decreases. And the stable flames can be established using NG and AOG as reformer fuel in the perforated ceramic burner. In particular, the blue flame is found to be stable at a lean equivalence ratio under different mixture conditions of NG and AOG for the 0.5 to 1.0 kW fuel cell system power range. NOx emission is under 60 ppm between 0.70 to 0.78 of equivalence ratio and CO emission is under 50 ppm between 0.70 to 0.84 of equivalence ratio.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.477-480
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• 2006

In this study, we investigated operating characteristics of the LNG burner for steam methane reforming. The developed LNG burner and catalytic reactor to supply an efficient heat transfer between the combustion gas and catalyst got a good response of various operating load within 5-7 minute and high efficiency for steam methane reforming as a conversion of methane over 90%. We calculated the volume of catalyst for $1Nm^3/hr$ steam LNG reforming as $211cc/(Nm^3/hr\;H_2)$ and got the operating condition and design data of the burner and steam reforming for LNG.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.7
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• pp.997-1004
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• 2001

Burner of Flat Flame type expects the uniform flame distribution and NOx reduction. The characteristics of Flat Flame Burner become different according to swirl number in the burner throat. Experiments were focused on swirl effect by four types of swirler with different swirl numbers (0, 0.26, 0.6 and 1.24). It shows many different flow patterns according to swirl number using PIV(Particle Image Velocimetry) method. The flow of burner with swirler is recirculated by pressure difference between its center and outside. Recirculated air makes stable in flame, and reduced pollutant gas. In case of swirl number 0, main flow passes through axial direction. As swirl number increased, The backward flow develops in the center part of burner and Flow gas recirculates. This is caused by radial flow momentum becomes larger than axial flow by swirled air and the pressure at center drops against surrounding. As swirl number increases, the radial and axial velocity was confirmed to be larger than low swirl numbers. And turbulence intensity have similar pattern. The CTRZ(Central Toroidal Recirculation Zone) is shown evidently when y/D=1 and S=1.24. The boundary-layer between main flow and recirculated flow is shown that the width is seen to be decreased as swirl number increased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.2
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• pp.235-243
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• 2001

This paper describes a design study of the cylindrical multi-hole premixed burner to be used for condensing gas boiler which can raise performance and reduce NOx emission. In this study, specifications of the multi-hole burner (hole diameters and arrangement) are investigated using model flat burners in terms of flame stability, and combustion characteristics for stability and NOx emission are examined for cylindrical multi-hole burner. As a result, the equivalence ratio for optimum operation condition of the cylindrical burner is around 0.72(0.7∼0.75). In this condition, turn-down ratio becomes 3 : 1 at least which is suitable for proportional control. The NOx and CO emission is less than 40ppm and 25ppm(0$_2$0% basis), respectively. This burner can be applied LPG as well as NG because there is no difference for stable combustion region.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.111-115
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• 1999

In order to enhance the burner performance of household gas fired absorption chiller/heaters, the operating condition(excess air $\approx$ 10%) of the burner currently being used was required to be optimized. In this regard, we examined where the $CO_{\min}$. emission limit was located between blow off and yellow tip limit and how much amount of excess air was exhausted by means of observing blow off and yellow tip limit. It was found that the $CO_{\min}$ limit(excess air ${\approx}$ 4%) was determined near the yellow tip limit. The effect of exhaust pressure on the $CO_{\min}$. limit was that, if exhaust pressure was higher than that in steady condition, higher air blower fan rpm is demanded to maintain the $CO_{\min}$ limit. Therefore, it was necessary to optimize the operating condition of burner in terms of a thermal efficiency and safety.

• Journal of the Ergonomics Society of Korea
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• v.30 no.3
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• pp.389-394
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• 2011

The aims of this study are to investigate the Korean population stereotype for control-display linkage of four-burner gas-range, and to compare the results of this study with those of the existing studies. The investigation used a paper-pencil test using questionnaire with a sign code system for eliminating suggestive effect of sequential code. Two hundreds and eighty subjects participated in the investigation, among whom 254 subjects effectively responded to question for the gas-range stereotype. The results showed that type III(refer to Table 2) was chosen more frequently than type II, IV and V(p<0.01). The gender is not significant on responding rate for the type of control-burner linkage(p>0.92), while the age and occupation have significant effect on the rate(p<0.01). Based on this study, it appears that type III represents the population stereotype of control-burner arrangement for Korean. The stereotype was the same as that of Chinese, but different from that of American(type II or IV). The findings of this study would be helpful as basic data for ergonomically designing gas-range or similar products.

• 연구논문집
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• s.27
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• pp.101-108
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• 1997

The characteristics of combustion and emissions in multi-staged oil burner have been experimentally studied for the various range of equivalence ratios, drop sizes and fuel formulations. Malvern system was used to measure droplet size of fuel. Light fuel oil and light fuel oil doped with pyridine($C_5H _5N$) were used to investigate the effects on fuel NOx emission. The emissions of NO and CO in exhaust gas and the flame temperatures were measured by the gas analyzer and thennocouples. NOx emissions were increased by increasing the excess air ratio (range:$lambda=1.1-1.4$) or decreasing the SMD of droplet in single-staged burner. In comparison with the single-staged burner, the emission of NOx in multi-staged burner was reduced by 50% but CO emission was slightly increased. It is found that multi-staged burner has a good capability in reducing thermal NOx resulting from the distributed heat release rate and lower flame temperature in fuel-rich and fuel-lean combustion zone. Moreover, the fuel NOx emission of the multi-staged burner is lower than that of single-staged burner, because multi-staged burner has fuel rich zone where fuel N is converted to $N_2$ more than NO. In 3-staged burner, the percentage of each stage combustion air have strong influence on emission characteristics. It is also found that NOx emission can be reduced by decreasing inner and outer air percentage or increasing middle air flow rate and CO emission is vice versa.

• Journal of Energy Engineering
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• v.26 no.2
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• pp.23-31
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• 2017

Numerical study was conducted for the effects of various burner array on the workpiece and the gas temperature in a continuos reheating furnace. Under the same conditions which were the total heat of combustion, the heat capacity of unit burner, the number of burner and burner array were changed to be applied the furnace. The behavior of workpiece temperature and gas temperature in a furnace were evaluated for the effects as function of the changed conditions. A continuous reheating furnace designed for 110 tons/day of production capacity was applied in this study. The furnace which has several gas burners is designed to heat a workpiece. By this study, the better condition was confirmed than the existing designed condition.