• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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• pp.141-148
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• 2004

Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a few basic analysis and thermo-gravimetric analysis. It was found that coke has a higher reactivity than anthracite due to the difference of surface area and density. Those characteristics are reflected to the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion, which implies the further investigation should be performed for obtaining optimal combustion conditions in the sintering bed.

• 한국연소학회지
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• 제7권1호
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• pp.52-57
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• 2002

A numerical investigation using a commercial CFD program of the Inter-Phase Slip Algorithm has been carried out for detail characteristics of particle motions and bubble behaviors in a two dimensional fluidized bed. The bed simulated has been operated with three different distributor geometries, such as bubble cap, nozzle, and perforated plate types. Experiments using a slit-type two-dimensional fluidized bed and a cylinder-type fluidized bed have been performed in order to confirm the simulation model. In addition, the numerical results are compared with the wellknown correlation of bubble sizes and bubble rising velocities by Mori and Wen [1]. The simulation model that we applied is shown to be useful to understand the relation between bubble behaviors and distributor geometries.

• 아시안잔디학회지
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• 제11권3호
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• pp.193-203
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• 1997

This study was carried out to investigate the phytosociological method for analyzing vegetation composition, which would be one of the major keys of land use in Sinchun stream side-bed. The obtained results were as follows As the result of survey, following flora were observed. Most of plants composed of Graminea,Compositae, Leguminosae and Poligonaceae, 23, 17, 13 arid 9 species, respectively. In upper stream side-bed, E crus-galli var. caudata and Phragmites communis were well growed,which were effective for cleansing water. Otherwise both Polygonum species and Rumex were profused in Mid-stream side-bed and Down-stream side-bed, these plants were well growed in polluted stream. Key words: Phytosociological, Polluted stream, Sinchun stream side-bed, Taegu city.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.651-655
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• 2000

The objective of present work is to investigate experimentally the characteristics of heat transfer. A fluidized bed combustion has advantages of pollution control, fuel flexibility and excellent heat transfer. The present study investigates fundamental phenomena of bed-to-surface heat transfer in high temperature fluidized beds to improve design of immersed tube surface. The tested operating variables are bed temperature, supeficial velocity, mean size of bed material, and the rake angle of fin. Generally, heat transfer rates between the fluidized bed and immersed finned-tube are much higher than those of a smooth tube. A life time of finned-tube is generally longer than that of smooth tube.

• 한국대기환경학회지
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• 제20권3호
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• pp.361-369
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• 2004

A metal fiber bed has seldom been applied to the practical filtration process despite its excellent mechanical and chemical stability. The filter-bed used in this work was highly porous with open structure, of which apparent porosity was 80 ∼ 90%. Although pressure loss across the filter-bed was very low, separation efficiency was found to be quite high. This paper focuses on the basic filtration mechanisms of a metal filter-bed and a thin ceramic filter from fly ash for reference. The experimental parameters were face velocity, dust loading and porosity of filter-bed. Pressure drop increased with increasing face velocity and dust feeding load for both filters. It also showed that dust particles deposited in the deep flow path, finally resulting in clogging the pore channels. It thereby indicates that the dominating mechanism of the metal filter-bed would be depth filtration. Meanwhile, the thin fly ash composite filters trapped the aerated dust mainly on the surface of the filter medium, so that the instantaneously formed dust layer might cause a steep increase of pressure drop across the filtration system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.26-27
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• 2014

This paper proposes a new bed stage system for vibration attenuation in patient compartment of ambulance. The bed stage which consist of four MR dampers can isolate vibration in the vertical, rolling and pitching directions. After evaluating dynamic characteristics of MR damper, 1/4 bed stage model is formulated. The sky hook controller is then utilized for vibration control. Finally, control responses of the bed stage equipped with MR dampers are presented.

• 열처리공학회지
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• 제6권4호
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• pp.243-248
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• 1993

A Circulating Fluidized-Bed (CFB) with an internal nozzle and a partition wall was proposed. The technique of fluidization is related to operations first used commercially in the fields of metallurgical and mechanical engineering such as the heat treatment of metals and power station combustors. In the modified CFB, an internal nozzle and a partition wall were additionally set in the main bed. This cold mode CFB apparatus made of acrylic resin; the main bed is 1,500mm high and 100mm in the inner diameter, the internal nozzle is 130mm high and 10mm in the inner diameter, and the partition wall is 7mm thick and 100mm in the diameter. Glass beads of $89{\mu}m$ in the mean diameter were employed as bed materials.

• 설비공학논문집
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• 제7권3호
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• pp.450-460
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• 1995

A modified circulating fluidized bed heat exchanger under severe fouling condition is developed. The effects of fouling deposits on the performance of a heat exchanger are investigated. The principle and operating characteristics of a circulating fluidized bed heat exchanger are dicussed. A modified circulating fluidized bed heat exchanger shows more stable operating than the other circulating fluidized bed heat exchanger. The characteristics of self cleaning and heat transfer enhancement of a circulating fluidized bed heat exchanger are studied. The movement of spherical particles in a tube is visualized and heat transfer enhancement and scale reduction mechanism by particles are investigated.

• 대한임베디드공학회논문지
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• 제9권3호
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• pp.165-171
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• 2014

In this paper, we propose the hardware and software of a test-bed of a hovering AUV (autonomous underwater vehicle). Test-bed to develop as the underwater robot for the hovering -type is planning to apply for marine resource development and exploration for deep sea. The RTU that controls a azimuth thruster and a vertical thruster of test-bed is a intergrated-type thruster. The main control unit that collects sensor's data and performs high-speed processing and controls a movement of test-bed is a underwater hybrid navigation system. Also it transfers position, posture, state information of test-bed to the host PC of user using a wireless communication. The host PC checks a test-bed in real time by using a realtime monitoring system that is implemented by LabVIEW.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제11권1호
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• pp.7-14
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• 2005

The existing six-bed patient rooms, general type of multiple-bed rooms in Korea causes many problems for the amenity of patients. We should reconsider their inconvenience carefully and try to provide the right to keep their privacy and enjoy amenity. The number of patients of multi-bed rooms is very critical point to improve the environmental condition of the patient rooms. So This paper aims to provide the possibilities of four-bed rooms through the comparison and analysis of six and four-bed room for planning and design.