• Journal of Mechanical Science and Technology
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• v.15 no.2
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• pp.239-247
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• 2001

Measured radiative heat fluxes on the furnace exit plane of a heavy duty power boiler of steam output 1650 T/h are discussed. A high-ash pulverized bituminous coal was used. Such measurements are necessary to improve heat fluxes inside a steam boiler furnace was manufactured. An extra small heat radiation sensor was placed in the water cooled head of the probe. The sensor had no direct contact with furnace gases and measured only the radiant energy. There was no exposure to convective heat transfer. With the radiometric probe, one can obtain a spherical indicatrix of radiation intensity as well as hemispherical radiative heat flux incident on any surface passing through a measuring point inside the furnace. Thus, the quantity of radiation energy, passing through the furnace exit plane, to the convective heating surfaces and the quantity of radiation energy going in the opposite direction were measured. A formula for relative radiative heat flux on the furnace exit plane has been proposed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.107-110
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• 2004

Application of aluminum alloy has been increasing for most of industry area because aluminum has a good mechanical properties and castability, especially automotive field for weight reduction. But, Furnace industry is sluggish. The purpose of this study is numerical analysis of aluminum holding furnace for reasonableness estimation when we design for new model of furnace. The numerical simulation involving fluid flow of inside air and heat transfer to fireproof material is presented in order to improve the understanding of aluminum furnace. First of all, we are carried out numerically for the two dimensional inside convection and surface radiation heat transfer in a square enclosure. Subsequently, we are established the analysis method of aluminum furnace considering natural convective heat transfer

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.943-944
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• 2008

In this paper, image processing technologies was employed to monitor and visualize the conditions of the inside of furnace for glass. In order to capture the images of the furnace under the high temperature environment, specially designed camera system was used. From the experimental results we see that the developed software showed good information about the inside conditions such as a scum line and positions of bubbles.

• Journal of the Korean Society of Systems Engineering
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• v.12 no.1
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• pp.113-120
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• 2016

Steel in a continuous reheat furnace is heated to higher temperature to be treated in the rolling steel process. Due to this reason the continuous reheat furnace system requires an optimal control system to adjust the temperature inside the furnace. Level 2 control systems for continuous reheat furnaces generate automatic heating set points for the level 1 system of the furnace based on the mathematical thermal model which can give a good estimation of steel heating inside the furnace and is used to adjust heating requirements to optimize furnace combustion. For the current study the analytic methodology based on the design procedure from the systems engineering to develop new level 2 control system of a continuous reheat furnace was proposed. The system analysis and the requirements of the level 2 control system were derived using the unified modeling language (UML) 2.0, and the design of database and the graphic user interface (GUI) for the level 2 control system were conducted.

• 한국연소학회:학술대회논문집
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• 2004.06a
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• pp.248-255
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• 2004

For the compactness of regenerative combustion, self regenerative combustion and embedding regenerator inside furnace are proposed. The Self Regenerative burner system was developed to enhance thermal efficiency and Low Nox emission. In the twin regenerative system, two burner heads are generally used for preheating and exhausting combustion mode. But self regenerative burner system use only single nozzle body for regenerative combustion. Also two kind of regenerator, internal and external type, were designed to operate conveniently in both large and small furnace. According to test result, the self regenerative combustion system gives strong internal exhaust gas recirculation that reduce NOx emission significantly. NOx was measured as 50ppm(5% O2, 1290C furnace temperature). Also it is found that the fuel saving rate due to the self regenerative burner system reach to 30-40%. Thus it can be concluded that self regenerative mild combustion system appears to provide a reasonable regenerative burner for compactness and high performance as compared with conventional twin regenerative burner system. Also in the RT Application , compact twin regenerative burner was developed with the help of embedding regenerator inside furnace.

• Resources Recycling
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• v.18 no.3
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• pp.42-48
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• 2009

Since there are $OH^-,\;[SiO_4]^{4-}$ ion of high concentration at early hydration in the system added with activator (NaOH+$Na_2OSiO_2$) in the blast furnace slag, different from cement hydration, hydration progresses fast without induction period and forms reaction rim around the blast furnace slag grain. $0.6{\mu}m$ reaction rim was formed around the blast furnace slag grain from the 1 day of reaction period, and the thickness of reaction rim increases over the reaction time, growing to $1{\mu}m$ on the 28 days. Unreacted blast furnace slag grain deformed from angular shape to the spherical shape. Mole ratio of Ca/Si tends to decrease from inside of blast furnace slag grain to reaction rim. Difference of Ca/Si mole ratio between reaction rim and inside the blast furnace slag grain decreased and generated hydrate was a poor crystalline CSH(I) with Ca/Si mole ratio less than 1.5.

• Solar Energy
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• v.18 no.1
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• pp.81-89
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• 1998

In this paper an experimental was done to design combustion chambers which is required radiation strength of high temperature generator of absorption rigerator. Partiqularly, in combustion chamber radiative mediums were set and basic experiments were done according to its size by radiation strength and effects of heat transfer promotion. The results are as follows : 1) When radiative mediums were set in small combustion furnace burning nonframely radiative heat transfer was effected. 2) In case that area ratio($A/A_o$) of radiative medium is 0.82 or over, temperature fluctuation effects of furnace inside were not nearly. 3) In experimental boundary heat transfer effects were 1.8 times by setting up radiative medium. Specially, $q/{\Delta}T$ values of furnace inside were uniformed nearly by setting up radiative mediums.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.203-205
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• 2014

This paper is suggesting about glass melting technology, using both plasma and combustion heat source. The mixed flame was formed to flow pattern of turning by plasma and combustion in melting zone. The burning time was extremely extended for vitrification of raw materials in melting zone, as a result, meting time was significantly reduced. This system was designed to smaller size than existing glass melting facilities. We had achieved to 30% energy saving, due to reduce residence time of melted materials inside furnace.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.229-234
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• 2006

The oxy-fuel combustion heating characteristics is investigated experimentally by measuring furnace and steel temperature variations for batch type furnace simulator with a specially designed low NOx oxy-fuel burner. Economics of using oxy-fuel combustion is confirmed and, the furnace and steel temperature variations for different heating conditions are compared to deduce optimal heating control pattern for energy savings and rapid uniform heating. High $CO_2$ concentration (> 80-90%), low NOx (< 40ppm) and CO (< 10ppm) are measured in the flue gas. Temperature differences (< $30^{circ}C$) inside the furnace and steel are reduced relatively by increasing the burner jet momentum.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.10
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• pp.515-519
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• 2015

Conjugate heat transfer analysis for an ethylene furnace was carried out based on numerical simulation. Detailed distributions of velocity vectors, chemical species, and temperature inside the furnace are presented and discussed. Von Mises stress and heat flux at the tube surface were also evaluated to elucidate mechanisms regarding failure of the tube. Maximum stress was found at the upstream elbow of the tube, which did not coincide with the location of maximum heat flux. This implies that thermal stress at a steady state would not be a dominant component of the stress. Degradation of the material, as well as the system arrangement, should be considered in order to accurately predict the lifetime of the tube material in the furnace.