• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 추계학술대회 논문집
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• pp.423-424
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• 2000

상대적으로 낮은 미세입자(주로 10$\mu$m이하) 제어효율은 기-고 싸이클론의 최대 약점으로 논의되어 왔다. 이전 연구에서 싸이클론의 유출가스에 포함되어 있는 미세분진 입자들을 2차적으로 분리하고 제거할 수 있는 Post Cyclone(PoC)이라는 장치를 개발하여 그 효용성을 입증하였고(Hoffmann,1996), Mita 등(Mita el. al., 1997)이 이론적 뒷받침을 위한 연구를 진행하여 이론적 모델을 제시하였다. 즉, PoC의 효율은 Reynolds 수와 Stokes 수의 함수로 표시될 수 있을 것으로 추정하였다. (중략)

• 한국산업융합학회 논문집
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• 제21권3호
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• pp.133-139
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• 2018

Precipitator is the most widespread device used to separate dust particles from the exhaust gas. In the shipyard, welding umbrellas, spark protection covers, and ventilators are not purchased and used for the work place to capture the flames and high temperature metal dust generated during the gardening process. In particular, a thorough analysis of design factors, such as capture rate, collection capacity calculation, filter speed, and materials selection, is required since spatial constraints are followed by structures, etc. In this study, conceived to address problems such as this cyclone and filtration filter system that combines all-in-one gausing collector prototype. Assessed through interpretation through the validity of the design and reliability.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.585-586
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• 2009

• 한국입자에어로졸학회지
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• 제15권4호
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• pp.139-148
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• 2019

This study was performed for the application of a high-speed centrifugal cyclone to shale gas mining process. This device uses the centrifugal force to control particles similar to typical cyclones, and the disk located inside the cyclone is forced to rotate using a motor. The pressure difference occurred during the rotating of disk. Hence, inflow rate was generated without a blower fan. In addition, flow rate increased with elevating rpm of motor. The installing the disk in multiple stages on the inner rotor increased the instantaneous disk outlet flow. Hence, the control efficiency of oil particle increased from 1.05% to 31.2%. By modifying the structure of the disk so that the air flow to the opposite direction of the cyclone, the control efficiency of oil particles increased to 81.5%. By increasing the capacity of the motor and the size of the disk, the flow rate was increased to 2.5 ㎥/min because the rpm of motor and pressure difference increased. As rpm of motor increased, the cut-off diameter (d_pc) became smaller. Unlike the Lapple's equation, d_pc was inversely proportional to the effective number of rotations (N_e). The control efficiency was maintained even if the concentration of oil particles increased, for this reason, the higher the oil concentration, the more particles were accumulated and controlled.

• 한국생산제조학회지
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• 제22권2호
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• pp.223-227
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• 2013

Dust collecting performance of cyclone collector for oil mist was alalyzed in the study. The purposes of using cutting fluid during cutting have been colling, lubricating, chip washing and anti-corroding. However, the present manufactaring industry restricts the use of cutting fluid because cutting fluid confains poisonous substances which are harmful to the human body. Also, the optimum design oil-mist collector. The new oil mist collector was designed. In the near future, this device must be tested in the real machining center and CNC machine. Cutting using oil-mist showed better cutting characteristics than dry, air and fluid cutting with respect to by cutting force, tool wear and surface roughness. The model(A, B Type cyclone) of the set of fixture and alveolus are made by using a CAE software. Finally, we have obtained a model A Type solution by using orthogonal array. Therefore, it could be confirmed that as the model-A was increased and model-B was decreased, cut diameter was decreased.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.22-28
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• 2008

A closed type crankcase ventilation system has been adopted to engines to prevent emission of blow-by gas to atmosphere. In the early closed type crankcase ventilation system, blow-by gas which contains engine lubricating oil is re-circulated into the intake system. The blow-by gas containing oil mist leads to increased harmful emissions and engine problems. To reduce loss of the engine oil, a highly-efficient oil separation device is required. Principle of a cyclone oil separator is to utilize centrifugal force in the separator and, therefore, oil separator designs depend on rotational flow which causes the centrifugal force. In this paper, flow characteristics and oil separation performances for cyclone type designs are calculated with CFD methodology. In the CFD model, oil particle was injected on a inlet surface with Rosin-Rammler distribution and uniform distribution. The major design parameters considered in the analysis model are inlet area, cone length and outlet depth of the oil separator. As results, reducing inlet area and increasing cone length increase oil separation performance. Changes in outlet depth could avoid interference between rotational flow and outlet flow in the cyclone oil separator.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2001년도 추계학술대회 논문집
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• pp.101-102
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• 2001

Monodisperse aerosols containing spherical particles of known size, shape and density are the most widely used to calibrate particle-size measuring instruments and to determine the effects of particle size on the sampling device. However, these tests are time-consuming because monodisperse aerosols with different particle sizes are generated and tested in a series of experiments. Polydisperse aerosols may be used to determine the calibration or to simulate equipment under controlled laboratory condition. (omitted)

• 한국산학기술학회논문지
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• 제19권1호
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• pp.25-33
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• 2018

화석 연료의 고갈과 온난화 현상으로 인해 새로운 에너지원에 대한 관심이 급증하고 있다. 그 중에서 바이오가스는 유기성 폐기물 및 바이오매스를 혐기성 소화과정인 가수분해(hydrolysis), 산발효(acidogenesis), 유기산발효(acetogenesis), 메탄발효(methanogenesis)의 단계를 거쳐 발생되기 때문에 친환경적인 에너지자원으로 각광받고 있다. 그러나 바이오가스는 기존의 정제설비로는 제거할 수 없는 높은 미세분진 및 수분 함량으로 인해, 직접연소, 도시가스, 자동차용 연료 등 효율적인 이용을 위해서 정제시스템이 필요하다. 따라서 본 연구는 미세분진과 수분을 동시에 제거할 수 있는 정제과정의 전처리 방법으로써 원심력을 이용하는 냉각공정을 설계하였다. 원심력을 이용하여 분진을 제거하는 Cyclone 내 외부에 열교환기와 ID fan을 구성하여 주입되는 가스를 어는점 이하로 냉각시킴으로써 물안개를 형성시켜 분진입자를 제거하고, 일부 가스를 ID fan을 이용하여 재순환시켜 제거하는 고효율 냉각제어공정을 개발하였다. 수분제거는 유량(25~150L/min) 및 상대습도(60~95%)의 조건에서 시험하였다. 수분제거율은 상대습도 $95{\pm}5%$일 때 평균 80.8%, 입자제거율은 입자크기 $2.5{\mu}m$에서 평균 99.78%의 제거효율을 보였고, 수분과 입자의 동시제거효율은 수분 70.86%, 입자 99.67%의 평균값을 보여주었다.

• 한국대기환경학회지
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• 제27권6호
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• pp.641-649
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• 2011

The aim of this study is to understand the characteristics of exhausting particulate matters (PM) and to control emitted PM from meat cooking restaurants. We found that $PM_{2.5}$, $PM_{5.0}$ occupy 69.2% and 98.6% of total PM from pork cooking, respectively. Therefore, we can see that it is not easy to remove PM generated from a pork cooking process. The collection efficiencies of various control devices, which are a condensing scrubber, a cyclone, an impactor, an oil filter and an electrostatic precipitator (ESP), were measured and compared. ESP had the highest collection efficiency (88.6%) and condensing scrubber had the lowest one (68.0%). However, the system recovering property should be considered to choose a control device because PM from meat cooking process are extremely stickiness. Therefore, we can recommend that ESP following an impactor or a cyclone is the best combination to remove PM generated from meat cooking restaurants.

• 한국정보통신학회논문지
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• 제15권12호
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• pp.2632-2640
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• 2011

본 논문은 다수의 프로세싱 유닛의 데이터 처리할 수 있는 메모리 제어기를 설계하였다. 메모리 제어기는 마스터 중재기에 의해 마스터들의 요구 신호를 받아 순서에 맞추어서 데이터 충돌 없이 메모리에 전송하는 역할을 한다. 구현된 메모리 제어기는 마스터 인터페이스, 마스터 중재기, 메모리 인터페이스, 메모리 가속기로 구성된다. 제안한 메모리 제어기는 VHDL을 이용하여 설계하였고, 삼성의 메모리 모델을 이용하여 동작을 검증하였다. FPGA 합성 및 검증을 위해서는 ATERA사의 Quartus II를 이용하였고, 구현된 하드웨어는 Cyclone II 칩을 사용하였다. 시뮬레이션을 위해서는 Cadence사의 ModelSim을 이용하였다.