• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.187-194
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• 2004

The surface flames in porous ceramic burner are experimentally characterized to investigate the effects of equivalence ratio and firing rates. The results show that the surface flames are classified into green, red radiant and blue surface flame as the decrease of equivalence ratio. And each flame is maintained very stable and represents the same flame characteristics at any orientation of ceramic burner. Particularly the blue surface flame is found to be very stable at very lean equivalence ratio at 7000kcal/hr to 20000kcal/hr firing rates. And the exhausted NOx was analysed to find out which flame has lower NOx emission. The blue surface flame shows the lowest NOx emission regardless of the location of burner since it sustains very stable at lean mixture ratio.

• Journal of the Korean Society of Combustion
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• v.6 no.1
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• pp.29-35
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• 2001

The surface flames in porous ceramic burner are experimentally characterized to investigate the effects of equivalence ratio and firing rates. The results show that the surface flames are classified into green, red radiant and blue surface flame as decrease of equivalence ratio. And each flame is maintained very stably and shows the same flame characteristics at any orientation of ceramic burner. Particularly the blue surface flame was found to be very stable at very lean equivalence ratio at 200 to $800\;kw/m^2$ firing rates. And the exhausted NOx was analysed to find out which flame has lower NOx emission. The blue surface flame showed the lowest NOx emission regardless of the location of burner since it sustained very stable at lean mixture ratio.

• Journal of the Korean Society of Combustion
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• v.10 no.1
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• pp.7-12
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• 2005

The surface flames in perforated ceramic burner are experimentally characterized to investigate the effects of equivalence ratio and heating rate. The results show that the surface flames are classified into green, red radiant and blue surface flame as the decrease of equivalence ratio. Each flame is maintained very stable at the specified equivalence ratio and represents the same flame characteristics at any orientation of ceramic burner. Particularly the blue surface flame is found to be very stable at very lean equivalence ratio at 7000kcal/hr to 20000kcal/hr heating rates. And the exhausted NOx measurement shows that blue surface flame represents the lowest NOx emission regardless of the location of burner since it sustains very stable at lean mixture ratio.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.189-195
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• 2004

It compared quality characteristics for the stone surface treatment system and its products. With the result, the flame burner equipment was mainly used to the surface treatment of granite, but it occurred greatly the high temperature, the rock fragment, the noise and dust. For the other side, the whetstone polishing machine for the polishing was a maintenance for the specific physical properties of stone, and it did not occur the stone fragment and the dust. The durability of the stone products due to the flame burner was investigated with that it falls to $20\sim25\%$ more than the surface treatment by the whetstone polishing. Share's hardness of the polishing products in the durability test showed more greatly index than the flame burner and conventional product. The polishing products of Pochon stone in the case of the abrasion resistance showed great more $15\%$ than the general products, more $9\%$ than the products by the flame burner.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.10
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• pp.1033-1040
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• 2011

The premixed burner is a very strong candidate for using household boiler burner system because it has high efficiency, low emission and can be used in compact boiler system. Usually, household boiler burner systems use a Bunsen burner, which consists of an inner rich premixed flame and fuel burned completely by a secondary air supply. It has a relatively long flame length and operates in a high excess of air, so it is difficult to fit such a burner into a high efficiency compact boiler. In this paper, the characteristics of a premixed combustion burner for surface media such as metal fiber, ceramic, and SUS fin were evaluated. In particular, the flow velocity over the burner surface for the cold flow characteristics of the surface material were measured and adjusted. The combustion tests were carried out by taking pictures of the flame and measuring the flame temperature. The amounts of CO and NO were measured and the characteristics of the surface burner materials, combustion chamber, and heat exchangers were evaluated for various excess air ratios and heating values.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.3-6
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• 2012

Analysis method for the radiation heat transfer from the duct burner flame to the heat exchanger in a Heat Recovery Steam Generator (HRSG) was presented to supplement the existing thermal design process. Flame on a burner and a heat exchanger were postulated as imaginary planes and flame temperature, surface and emissivity was simplified in a aspect of engineering approach. The calculated local flame radiative heat flux on the heating surface was compared with the heat flux of 3-atomic gas radiation and convection.

• Journal of the Korean Society of Combustion
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• v.13 no.4
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• pp.26-36
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• 2008

Experimental study is conducted to identify the existence of a shrinking flame disk and to clarify its flame characteristics through the inspection of critical mole fraction at flame extinction and edge flame oscillation at low strain rate flames. Experiments are made as varying global strain rate, velocity ratio, and burner distance. The transition from a shrinking flame disk to a flame hole is verified through gradient measurements of maximum flame temperature. The evidence of edge flame oscillation in flame disk is also provided through numerical simulation in microgravity. It is found at low strain rate flame disks in normal gravity that buoyancy effects are importantly contributing to lateral heat loss to burner rim, and is proven through critical mole fraction at flame extinction, edge flame oscillation, and measurements of flame temperature gradient along flame disk surface.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.8-14
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• 2010

Fuel processing systems which convert fuel into rich gas (such as stream reforming, partial oxidation, autothermal reforming) need high temperature environment ($600{\sim}1,000^{\circ}$). Generally, anode-off gas or mixture of anode-off gas and LNG is used as input gas of fuel reformer. In order to make efficient and low emission burner system for fuel reformer, it is necessary to elucidate the combustion and emission characteristic of fuel reformer burner. The purpose of this study is to develop a porous premixed flat ceramic burner that can be used for 1~5 kW fuel cell reformer. Ceramic burner experiments using natural gas, hydrogen gas, anode off gas, mixture of natural gas & anode off gas were carried out respectively to investigate the flame characteristics by heating capacity and equivalence ratio. Results show that the stable flat flames can be established for natural gas, hydrogen gas, anode off gas and mixture of natural gas & anode off gas as reformer fuel in the porous ceramic burner. For all of fuels, their burning velocities become smaller as the equivalence ratio goes to the lean mixture ratio, and a lift-off occurs at lean limit. Flame length in hydrogen and anode off gas became longer with increasing the heat capacity. In particular, the blue surface flame is found to be very stable at a very lean equivalence ratio at heat capacity and different fuels. The exhausted NOx and CO measurement shows that the blue surface flame represents the lowest NOx and CO emissions since it remains very stable at a lean equivalence ratio.

• Journal of KSNVE
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• v.10 no.6
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• pp.991-997
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• 2000

The objective of this study is to examine the onset condition and the frequency characteristics of the low-frequency combustion oscillation in a surface burner. For this purpose, extensive parametric studies have been performed experimentally and the effects of size of each section, the equivalence ratio, and the entrance velocity on oscillatory behavior explored. The experimental results were discussed in comparison with the other combustors associated tilth the low-frequency combustion oscillation. The combustion mode is driven at high combustion rate by the lift of unstable flame near the lower limit of the combustible equivalence ratio. The oscillation frequency is dependent not on the burner geometry but on the equivalence ratio and the combustion load. Low-frequency combustion mode was formed to be divided into two different modes, named C1 and C2 respectively. Two modes occurred individually, simultaneously or transitionally according to the equivalence ratio and combustion load. The characteristics of low-frequency oscillation is different from each other depending on the type of combustors. The surface burner has also its own characteristics of low -frequency oscillation.

• Journal of the Korean Society of Combustion
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• v.14 no.4
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• pp.7-16
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• 2009

Porous metal plates (Metal fiber, muti-hole metal plate) using mainly in surface burner are known to have a corrosion and durability problem under high temperature condition. In this study, premixed flat flame with perforated ceramic tile of more durable cordierite material was examined with respect to combustion stability and emission. The flat premixed ceramic burner consists of perforated ceramic tile and various type of baffle plates to form stable surface flame. The results show that most stable flat flame is generated using baffle plate with open ratio of 0.193. In downward flat flame mode which is widely used in condensing boiler, CO is measured below 50ppm from equivalence ratio 0.755 to 0.765 and $NO_X$ is measured below 12ppm from equivalence ratio 0.75 to 0.79. It is also found that the range of blue flame in flame stability curve becomes wider with increasing heat capacity.