• 한국가스학회지
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• 제2권1호
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• pp.47-52
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• 1998

천연가스 공급배관내의 이물질을 제거하기 위하여 한국가스공사에서는 현재 250um 공극 크기를 갖는 금속 스트레이너형의 필터를 사용하고 있다. 하지만 배관내의 이물질 크기를 조사한 결과 필터 공극 크기보다 작은 이물질이 상당량 있는 것으로 파악되었으며. 따라서 이들 이물질로 인하여 필터 후단부의 각종 밸브류나 계 량 측정 기기들에 악영향을 미치고 있는 실정이다. 미세한 크기의 이물질들을 없애기 위해서는 필터의 공극 크기를 줄여야 하는데. 이 경우에는 필터 전, 후단의 차압발생으로 인하여 원하는 유량의 가스를 공급하기 어려운 일이 생길 수 있으므로 차압발생을 신중히 고려하여 필터 공극 크기를 결정하여야한다. 본 연구에서는 손실계수 K를 이용하여 가스필터의 성능평가 방법을 제시하였다.

• 한국세라믹학회지
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• 제49권3호
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• pp.226-230
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• 2012

This paper presents a novel structure for a diesel particulate filter (DPF) with inclined gas paths, which was designed so that the gas paths offered a fluent flow of exhaust gases, and particulate matter (PM) was collected at pores formed in the body. The alumina porous filter was prepared by a conventional sintering process at $1200^{\circ}C$ for 2 h. Straight gas paths with $30^{\circ}$ of inclination from the gas flow direction were formed in the filter body. It is shown that this filter structure worked as a PM filter, in which 90.2% of soot filtration efficiency and 59.6 mbar of pressure drop were achieved.

• 한국자동차공학회논문집
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• 제5권1호
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• pp.1-13
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• 1997

The key point that guarantees the durability of the ceramic monolith filter is to lower peak temperature and temperature gradient inside filter during regeneration. The control of the exhaust gas flow rate into the filter, by the bypass technique of the exhaust gas, enables the gas temperature in filter to be constant for regeneration. A couple of methods, which are the ON/OFF and PID control of the bypass valve, were used for feedback control of the gas temperature. These techniques showed that the ceramic filter was regenerated perfectly under the peak temperature and peak temperature gradient limitations for durability.

• 한국기계가공학회지
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• 제20권10호
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• pp.119-127
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• 2021

Small drops in gas cause some problems for downstream equipments such as turbine, compressor and etc. In some cases, we are obliged to remove hazardous liquid mist from gas. In order to remove water or other liquids from the gas, there are some equipments like mesh mist eliminator and vane-plate mist eliminator. oil mist filter is a kind of liquid eliminator equipments used to remove the liquid with 1-10um droplet diameter from the gas. In this paper is determine the factors affecting the oil mist filter efficiency using CFD. length and angle of the filter were considered and the results and compare the results of the efficiency tests, showed error of less than 3%. optimum filter can remove more than 87.3% between 1 and 10um of oil mist.

• Design & Manufacturing
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• 제16권1호
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• pp.15-20
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• 2022

This paper is about elimination the situation in which gas sensor data becomes inaccurate due to temperature control when a semiconductor gas sensor is driven. Recently, interest in semiconductor gas sensors is high because semiconductor sensors can be driven with small and low power. Although semiconductor-type gas sensors have various advantages, there is a problem that they must operate at high temperatures. First temperature control was configured to adjust the temperature value of the heater mounted on the gas sensor. At that time, in controlling the heater temperature, gas sensor data are fluctuated despite supplying same gas concentration according to the temperature controlled. To resolve this problem, gas and temperature are extracted as a data. And then, a relation function is constructed between gas and temperature data. At this time, it is included low pass filter to get the stable data. In this paper, we can find optimal gain and parameters between gas and temperature data by using genetic algorithm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.393-397
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• 2001

The innovatory process, that is the direct separation and recovery of the iron and zinc metals contained in the high temperature exhaust gas generated from the electric arc furnace fer the inn scrap melting and/or the dust treatment, has been proposed. This proposed process consists of the moving coke bed filter that is directly connected to the electric furnace, and the following heavy metal condenser. The exhaust gas passes through the filter and the condenser right after exhausting from the electric furnace. The moving coke bed filter is being controlled at about 1000℃ and collects iron and slag components contained in the high temperature exhaust gas. Heavy metals such as zinc and lead pass through the filter as vapor. Based on the thermodynamic considerations, the iron oxide and the zinc oxide are reduced in the filter. The solution loss reaction rate is comparatively low at about 1000℃ in the coke bed filter by the analysis using the mathematical simulation model. The heavy metal condenser is installed in the position after the coke bed filter, and rapidly cools the gas from about 1000℃ to 450℃ by a full of the cooling medium like the solid ceramic ball in addition to the cooling from the wall. The zinc and lead vapor condense and separate f개m the gas in a liquid state. The investigation of the characteristics of the exhaust gas of the commercial electric arc furnace, the fundamental experiments of the laboratory scale and the bench scale ensured the formation of this proposed process. A small-scale pilot plant examination is carrying out at present to confirm the formation of the process. It is certain that the dust generation of the electric arc furnace is extremely decreased, and it can save the energy consumption of usual dust treatment processes by the realization of this process.

• 한국자동차공학회논문집
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• 제24권5호
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• pp.549-555
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• 2016

This research was performed to determine the oil separation characteristics of the specially designed oil filter installed in a PCV cylinder head passage. The oil filter was specially designed with fleece for separating oil mist from blow-by gas. The fleece, made of fiber fabric material, is placed in the oil filter case to absorb oil mist with a small pressure drop during blow-by gas through the filter. To do this, 3-D CFD analysis was simulated for the simplified PCV system with the oil filter using the commercial code, Ansys CFX. Results showed that the oil filter's efficiency with fleece sharply increased as oil droplet size increased.

• 한국입자에어로졸학회지
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• 제5권4호
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• pp.159-170
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• 2009

A depth filter medium was newly designed in order to achieve high collection of dust and low pressure drop in this work. Multilayer depth filter media consist of an upstream layer of highly porous structure which allows particles to pass through and to follow by one or more downstream layers to hold the particles inside the media. For each filter media, flat sheet and pleated module were made of newly developed depth filter media and filter media of commercial products. Commercial depth filter cartridge for gas turbine air intake cleaning were used as reference for filtration area and pleat geometry of pleated modules. This work attempts to evaluate and compare the newly developed depth filter medium and two commercial filter media in terms of filtration parameters such as air permeability, initial pressure drop, particle retention and pressure drop variation with dust loading. According to the close examination the newly developed depth filter showed better performance compared to the commercial depth filter media.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.341-344
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• 2008

Computational studies have been performed to analyze the particle loadings onto the filters according to the different inflow pattern of dusty gas and the flow uniformities on the filter surface of back-blown gas at different permeability of porous media setup at the filter outlet. This is preliminary study to find how we can reduce the regeneration time and improve the regeneration efficiency of filters with dust layer.

• 한국자동차공학회논문집
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• 제5권4호
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• pp.130-141
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• 1997

Work on the reduction of particulate matter(PM) from a diesel vehicl has led to a new trp system and a control method to control the combustion rate of the PM filtrated in the trap, which was named as 'Active Exhaust Feeding Regeneration(AEFR) System' by its operation mechanism. Ceramic cordierite filter is a major component of the trap and susceptible to thermal shock. Therefore the system should be designed to reduce the peak temperature and temperature gradients in the trap ; these have been considered to be the main factors causing thermal shock of the filter during the regeneration. It uses the engine's exhaust gas partially for the regeneration of the ceramic filter. It controlled bypass flow rate of the engine's exhaust gas precisely to control the temperature of the gas entrained into the filter. Gas temperatures were measured inside filter, and the oxygen concentration at the outlet of the filter was also monitored during the regeneration to analyze the combustion process of the PM. The temperature distributions and temperature gradients in the filter during the regeneration varied widely according to the regeneration control schemes. Finally, this system shows relatively low peak temperature and temperature gradients in the filter during its regeneration. It is considered that this system uses a mew method to control the combustion rate of the PM, which is different from the methods used in the previous studies.