• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.9-13
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• 2012

In the iron ore sinter process, temperature distribution pattern in sintering bed is related with productivity and quality of sintered ore. Evenly heat distribution make the uniform quality of sintered ore but in normal operating condition, upper part of bed has lack of heat and scarce quality of sintered ore, thus yeild rate is decreased and productivity is diminished. Therefore, using the additional fuel for increasing quality and flue gas recirculation for increasing productivity are considered and effect of both processes are discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.9
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• pp.2916-2923
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• 1996

A numerical analysis of the moving bed heat exchanger of solid particles inside the vertical pipe was performed using finite difference method. Also, the theoretical solutions were obtained for comparison when the wall heat flux or the wall temperature was assumed constant. The comparison showed that their results agreed well each other. The moving bed heat exchanger was classified as countercurrent-flow, parallel-flow, and cross-flow types according to the gas flow direction. For each type, the thermal efficiency of heat exchanger was calculated as a function of non-dimensional parameters such as the characteristic length of heat exchanger, Biot number and the ratio of thermal capacities of gas and solid particles.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.21-24
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• 2012

In the iron ore sinter process, temperature distribution pattern in sintering bed is related with productivity and quality of sintered ore. Evenly heat distribution make the uniform quality of sintered ore but in normal operating condition, upper part of bed has lack of heat and scarce quality of sintered ore, thus yeild rate is decreased and productivity is diminished. Therefore, using the additional fuel in the upper part of bed is considered and effect of fuel is discussed. (max. 80 words).

• KSBB Journal
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• v.13 no.2
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• pp.141-146
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• 1998

To remove the low concentration of methane biologically, a three phase fluidized bed bioreactor immobilized with Methylosinus trichosporium OB3b was used. Optimum pH, temperature and bed height for the operation were pH7.0, 30$^\circ C$ and 150cm, respectively. For the inlet methane concentration of 100-400ppm and flow rate of 2-4L/min, the removal efficiencies of the bioreactor using the activated carbon as a carrier were the range of 54-71%, whereas those using the biosand were the range of 45-56%. It was found that activated carbon was more efficient than the biosand for the removal of methane. When aeration tank was equipped with the bioreactor, the removal efficiency increased to 6-13% and maximum removal rate obtained in the experiment was 1184mg.CH$_4$/min.

• Solar Energy
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• v.12 no.1
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• pp.88-94
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• 1992

A small-scale solar collector and tracking system, using a Fresnel lens of $0.5m^2$, and novel compact fluidized-bed solar receiver[FBR] of closed type has been developed for high temperature solar gas heating. The FBR was improved in carrying over of SiC powder and thermo-siphon effect. The maximum outlet air temperature of 1140K and the maximum thermal efficiency of 64% were obtained. The present FBR's operated efficiently at extremely high temperatures in comparison with conventional solar receivers, composed of flat or tubular solid surfaces.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.451-451
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• 2000

This study aims for the optimization of process conditions in a fixed-bed catalytic reactor system with a circulating molten salt bath, in which partial oxidation of propylene to acrolein takes place. Two-dimensional pseudo-homogeneous model is adopted with estimation of suitable parameters and its validity is corroborated by comparing simulation result with experimental data. The temperature of the molten salt and the feed composition are found to exercise significant influence on the yield of acrolein and the magnitude of hot spot. The temperature of the molten salt is usually kept constant. This study, however, suggests that the temperature of the molten salt must be axially adjusted so that the abrupt peak of hot spot should not appear near the reactor entrance. The yield of acrolein is maximized and the position and the magnitude of hot spot are optimized by the method of the iterative dynamic programming (IDP).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.3
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• pp.175-182
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• 1992

Freezing of the binary solution ($H_2O-NaCl$) saturating a packed bed of spheres is investigated experimentally. The system is cooled through its top surface, and the bottom is maintained at a temperature above the liquidus. Experiments are performed on the hypolutectic side, and the cold wall temperature is lower than the eutectic point. The effects of initial mixture concentration, superheat and glass bead diameter on temperature and concentration distributions are investigated. Supercooling was observed only at early times of the freezing process for experiments with 5% initial salt concentration. Flow visualization experiments and mushy-liquid interface position observations revealed natural convection in the liquid region. Remelting phenomena was not observed at both the solid-mushy and mushy-liquid interfaces.

• Laser Solutions
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• v.3 no.1
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• pp.21-28
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• 2000

Selective Laser Sintering (SLS) can produce three-dimensional objects directly from a CAD solid model without part-specific tooling. In this study, a simple rapid prototyping through selective laser sintering on brass powder is investigated using a Nd-YAG laser. Experiments are conducted to produce single lines on a powder-packed bed for various process parameters. Also, temperature distribution in the powder bed and the thickness of a melted line are predicted by finite element analysis. In the numerical analysis, the thermal conductivity of the brass powder which is obtained as a function of state and temperature is used.

• Journal of the Korean Society of Industry Convergence
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• v.21 no.5
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• pp.241-246
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• 2018

The engine cooling system is a device that keeps the temperature of the engine room at a proper level by driving the cooling fan when the engine room temperature that occurs during driving is above a certain temperature. Recently, the vehicle cooling system has been changed to electronic system. Therefore, in this paper, we will analyze the clutch operation characteristics for designing a superior electronic fan clutch. For this purpose, an electronic fan clutch was designed and a test bed for performance evaluation was constructed and analyzed.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.672-675
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• 2013

Fast pyrolysis of medium-density fiberboard was carried out using a fluidized-bed reactor under various conditions to find an optimum pyrolysis condition. When the pyrolysis temperature was varied between $425^{\circ}C$ and $575^{\circ}C$, the maximum bio-oil yield of 52 wt% was obtained at $525^{\circ}C$. The quality of the bio-oil product increased with increasing pyrolysis temperature. Pyrolysis at a high temperature removed significant amounts of oxygenates and acids, producing more valuable species such as aromatics and phenolics. The main gaseous products were CO and $CO_2$. The yields of CO and $C_1-C_4$ hydrocarbons increased with increasing the pyrolysis temperature.