• 전기학회논문지
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• 제62권4호
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• pp.523-528
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• 2013

In recent years, many efforts are increasingly being made to conserve the natural environment with enhanced emission standards and air quality standards. Also there are various methods necessary to be researched to minimize the emission of air pollutants. In particular, boilers of industrial facilities are major portions of the air pollution. The front duct which needs to be designed to reduce the gases to the electrostatic precipitator requires a bent tube, a reduction/extend tube and an auxiliary equipment, that is, a guide vane. This paper proposes an optimum design of the guide vane by a case study for electrostatic precipitator's flow uniformity. The operating conditions of this study are as follows: BMCR (Boiler Maximum Continuous Rate) and MGR (Maximum Guaranteed Rate) are 75%, 50%, and 30%; turbulent fluid dynamics model is based upon K-${\varepsilon}$ formulation. Presentation of the computed motion of particles is found to be quite useful to predict the precipitator performance by use CFD (Computational Fluid Dynamics).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1326-1327
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• 2008

Recently, the air pollution is supposed is to be the most serious environmental problem. Therefore, a small air cleaner is asked to make comfortable indoor environment for the moderns who have frequent indoor activity. In this study, without generating of the second pollution source, dust in the air and harmful microorganisms can be removed by the electric dust collecting technology which has high reliability and efficiency to be able to remove the impurities even though it is just 0.01${\mu}m$. Accordingly, power sources of the dust collector use, it is not inefficiency and offering to dust collector unstable. In order to overcome the point at issue, a this study, for power factor compensating use the PFC circuit, for removing the noise use EMI filter and for generating the hight voltage use the Cockcroft Walton Circuit. And we study power source on characteristic and improvement.

• 조명전기설비학회논문지
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• 제22권9호
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• pp.69-74
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• 2008

동절기 전차선의 서리와 결빙은 매우 심각한 문제를 발생시킬 수 있다. 팬터그래프의 집진 스트립의 기계적 표면과 전차선 사이에 서리 또는 결빙으로 인한 아크가 발생하게 된다. 이에 따른 전기적 저항은 팬터그래프와 전차선 사이의 전류의 풀질을 감소시킨다. 해빙시스템은 통절기 전차선의 서리와 결빙을 녹이는 역할을 한다. 해빙시스템의 원리는 전차선의 임피던스의 Joule열을 이용하여 서리와 결빙을 제거하는 것이므로 전차선의 온도는 인가전류가 증가할수록 증가하였으며, 풍속이 증가할수록 감소하는 것을 알 수 있었다.

• 한국전기전자재료학회논문지
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• 제36권5호
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• pp.474-481
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• 2023

This paper is an experimental study on the optimal operating conditions of direct charging type electrospray for particulate matter collection. To perform the research, a direct charging type electrospray visualization system was configured to photograph the spray shape of microdroplets, and experiments were performed with varying electrode distance, flow rate, and applied voltage, which are the main factors affecting the particulate matter collection efficacy. Through image processing, the total number of microdroplets according to each condition was analyzed, and the number of microdroplets with a diameter of 1.5 mm or less was confirmed. In addition, by calculating the number of microdroplets per power consumption according to the applied voltage, the optimal operating conditions were derived in terms of energy consumption efficacy, and the microdroplet size distribution was analyzed under the optimal operating conditions. As a result of the experiment, it was confirmed that the optimal operating condition was at a flow rate of 10 mL/min and a voltage of -20 kV in case of 5 mm electrode distance, and at a flow rate of 15 mL/min and a voltage of -30 kV in case of 100 mm electrode distance.

• 한국터널지하공간학회 논문집
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• 제4권4호
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• pp.343-353
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• 2002

최근들어 장대터널이 증가하여 환기시스템의 환기기 용량이 증대하게 되면서 환기방식이 다양화 되어 환기기 운전동력등 터널준공 후 유지관리의 중요성이 부각되게 되었다. 따라서 환기기 운전단계나 환기기 운전모드에 대한 연구의 필요성이 증대하여 본 연구에서는 기 개발된 일교통량의 변화 및 환기기 가동상태에 따라 비정상상태로 터널 환기를 해석할 수 있는 동적 시뮬레이션 프로그램에 의해서 집진기 방식과 수직갱방식에 대한 운전동력을 평가하여 최적운전 모드를 제안하였다.

• 한국입자에어로졸학회지
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• 제9권2호
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• pp.79-87
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• 2013

In this study, the characteristics of turbulent flow and collection efficiency for an one-stage electrostatic precipitator(ESP) with slit type collecting electrode for urban railway underground tunnels were obtained using computational fluid dynamics(CFD) commercial code FLUENT 6.3 and lab-scale experiments. The electrostatic precipitator was operated under high gas velocity(3~12m/s). Five different designs of collecting electrode, flat plate-type and a slit-type of 3mm, 5mm, 7mm and 10mm slit width and four various gas velocity(3, 6, 9, and 12m/s) were used and applied. A standard k-${\varepsilon}$ model in CFD commercial code FLUENT 6.3 was used for flow simulation. The flow simulation results showed that the turbulent intensity of flat plate-type was higher than slit-type under all gas velocity conditions and also the turbulent intensity of flat plate-type was increased continuously, but in case of slit-type was maintained at constant range. And, the turbulent intensity was decreased according to increasing of slit width. The experimental results showed that the collection efficiency of slit-type was higher than flat plate-type under all gas velocity conditions. And, over 6m/s gas velocity condition, the collection efficiency of 5mm and 7mm was highest, when compared to 3mm and 10mm.

• 한국입자에어로졸학회지
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• 제14권4호
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• pp.89-95
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• 2018

People's environmental concerns for fine particles in Korea lead to the strong necessity of improving the performance of environmental control systems. Wet electrostatic precipitators (ESPs) are considered as one of the alternatives to overcome the limit of previous dry ESPs, the re-entrainment of collected particles during rapping and back corona problem for high electrical resistivity dusts etc. In this study, a wire-cylindrical ESP with a thin water film has been developed. Particle collection characteristics were compared in the ESP with operations of water film on and off. Particle collection efficiencies at various applied voltages as well as voltage-current curves were almost the same in the ESP with and without a water film. Particle collection performance for PM1.0, PM2.5 and PM10 in the wet ESP with a water film was constantly maintained with operation time even in the high dust loading environment. This results indicate that a uniform water film in our wet ESP was successfully formed with a very thin layer without any dry spot and therefore could continuously clean the collected particles on the inner wall of the ESP without any performance degradation.

• 한국입자에어로졸학회지
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• 제16권4호
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• pp.119-130
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• 2020

In this study, we developed a separated two-stage electrostatic precipitator applicable in a subway air conditioning system. We studied the characteristics of collection efficiency of 0.3 ㎛ particle and ozone generation at different charger sizes and gaps of collector plates. Also, we compared the performance of the two-stage ESP to the MERV 10 filter with the removal efficiency of 10% used in actual subway air conditioning system. The maximum collection efficiency of 0.3 ㎛ particle was 93% at A charger (600 mm×250 mm×600 mm) and 84% at B charger (330 mm×280 mm×330 mm). Especially, with voltages applied to chargers with collection efficiency of about 80% or more, the ozone concentration of two different chargers was 5 ppb to 35 ppb. Finally, the filter quality of the collector developed in this study was 400 times higher than that of the MERV 10 filter. Therefore, it was concluded that the two-stage ESP could be a promising PM removal device suitable for subway air conditioning system.

• 공업화학
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• 제31권1호
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• pp.84-89
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• 2020

초미세먼지로 분류되는 PM_2.5 (particulate matter under 2.5 ㎛) 중에서도 특히 sub-micron 입자(0.1~1.0 ㎛)의 먼지는 브라운 운동(Brownian motion)으로 집진장치의 효율에 한계를 준다. 따라서 수산화나트륨으로 활성화된 알루미늄산나트륨(NaAlO₂)을 응집제(coagulant)로 선택하여 석탄을 사용하는 유동층 보일러에서 석탄의 회분에 포함된 칼륨(K)과 PM_2.5의 입도분포의 거동과 영향을 확인하고자 했다. 그리고 응집제를 석탄의 무게대비 1,200 : 1 비율로 석탄에 혼합 및 분사하면서 정상 운전하는 중에 보일러의 싸이클론에서의 미세먼지(FP)와 전기집진기에서의 미세먼지(EP)를 포집 및 고찰하였다. 포집한 미세먼지를 입도분석기를 이용하여 입도분포(%)를 분석한 결과 FP에서 평균 4.87%에서 0.51%로 변화를 보임으로써 89.53% 감소하였다. EP에서의 평균 3.46%에서 0.40%로 변화를 보임으로써 88.57% 감소하였다. 포집한 미세먼지를 XRP로 칼륨을 추적한 결과 칼륨의 변화율은 FP에서 평균 1.65%에서 1.87%로 13.33% 증가하고, EP에서 평균 1.65%에서 2.03%로 17.68% 증가하였다. TMS에 의해서 확인된 총 미세먼지 농도(mg/㎥)는 1차는 2.6 mg/㎥에서 1.7~1.9 mg/㎥로 26.9~34.6% 감소하였으며, 2차는 평균 2.9 mg/㎥에서 1.7~1.9 mg/㎥로 33.3~40.4%가 감소하였다. 따라서 본 연구의 응집제가 PM_2.5 초미세먼지 입자의 크기와 그로 인한 집진장치효율에 크게 영향을 미치는 것으로 확인하였다.

• 한국입자에어로졸학회지
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• 제14권4호
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• pp.171-180
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• 2018

To optimize the shape of the electrostatic precipitator for the removal of particulate matter in subway environments, the wind-tunnel experiments were carried out to characterize collection efficiency and ozone emission rate. As a standardized parameter, power consumption divided by the square of flow velocity, was increased, the $PM_{10}$ collection efficiency increased. If the standardized parameter is higher than 1.0 due to high power consumption or low flow velocity, increase in thickness of electrodes from 1 to 2 mm, or increase in distance of collection plates from 5 to 10 cm did not change the $PM_{10}$ collection efficiency much. Increase in thickness of high-voltage electrodes, however, can cause decrease in $PM_{10}$ collection efficiency by 28% for low power consumption and high flow velocity. The ozone emission rate decreased as distance of collection plates became wider, because the ozone emission rate per unit channel was constant, and the number of collection channels decreased as the distance of collection plates increased. When the distance of collection plates was narrow, the ozone emission rate increased with the increase of the thickness of electrodes, but the difference was negligible when the distance of collection plates was wide. It was found that the electrostatic precipitator having a thin high-voltage electrodes and a narrow distance of collection plates is advantageous. However, to increase the thickness of high-voltage electrodes, or to increase the distance of collection plates is needed, it is necessary to increase the applied voltage or reduce the flow rate to compensate reduction of the collection efficiency.