• 제목/요약/키워드: 입자침착

검색결과 81건 처리시간 0.022초

정전효과가 있는 가열 회전원판으로의 입자침착 해석 (Analysis on Particle Deposition onto a Heated Rotating Disk with Electrostatic Effect)

  • 유경훈
    • 설비공학논문집
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    • 제14권5호
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    • pp.424-432
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    • 2002
  • Numerical analysis has been conducted to characterize deposition rates of aerosol particles onto a heated, rotating disk with electrostatic effect under the laminar flow field. The particle transport mechanisms considered were convection, Brownian diffusion, gravitational settling, thermophoresis and electrophoresis. The aerosol particles were assumed to have a Boltzmann charge distribution. The electric potential distribution needed to calculate local electric fields around the disk was calculated from the Laplace equation. The Coulomb, the image, the dielectrophoretic and the dipole-dipole forces acting on a charged particle near the conducting rotating disk were included in the analysis. The averaged particle deposition vetocities and their radial distributions on the upper surface of the disk were calculated from the particle concentration equation in a Eulerian frame of reference, along with a rotation speed of 0∼1,000rpm, a temperature difference of 0∼5K and a charged disk voltage of 0∼1000V.Finally, an approximate deposition velocity model for the rotating disk was suggested. The present numerical results showed relatively good agreement with the results of the present approximate model and the available experimental data.

열영동력이 수평 웨이퍼상의 입자침착에 미치는 영향 (Thermophoretic Effect on Particle Deposition Toward a Horizontal Wafer)

  • 배귀남;박승오;이춘식
    • 대한기계학회논문집
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    • 제18권1호
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    • pp.175-183
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    • 1994
  • To investigate thermophoretic effect on particle deposition, average deposition velocity toward a horizontal wafer surface in vertical airflow is measured keeping the wafer surface temperature different from the surrounding air temperature. In the present measurement, the temperature difference is maintained in the range from -10 to $4^{\circ}$ C Polystyrene latex (PSL) spheres of diameter between 0.3 and 0.8 .mu.m are used for the experiment. The number of particles deposited on a wafer surface is estimated from the measurements using a wafer surface scanner (PMS SAS-3600). Experimental data are compared with prediction model results.

정전효과를 고려한 반도체 웨이퍼의 입자침착 특성 (Particle Deposition Characteristics with Electrostatic Effect on Semiconductor Wafers)

  • 이건형;채승기;문영준
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2006년도 하계학술발표대회 논문집
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    • pp.779-785
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    • 2006
  • Particle transport and deposition characteristics on semiconductor wafers inside the chamber were experimentally investigated via a particle generation & deposition system and a wafer surface scanner. Especially the relation between particle size($0.083{\sim}0.495{\mu}m$) and particle deposition velocity with ESA(Electrostatic Attraction) effect was studied. Spot deposition technique with the deposition system using nozzle type outlets of the chamber was newly conducted to derive particle deposition velocity and all experiment results were compared with the previous study and were in a good agreement as well.

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SEM/EDX를 이용한 서울시 지하철 역사 내 개별입자의 질량분율에 관한 연구 (A Study on Mass Fractions of Individual Particles by SEM/EDX in Seoul Subway Stations)

  • 한근혁;김동술
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2002년도 춘계학술대회 논문집
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    • pp.249-250
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    • 2002
  • 입자상 물질은 호흡에 의해 폐 깊숙이 침착되어 인체에 피해를 줄 수 있다 같은 질량의 거대 및 미세 입자가 있을 경우, 입자의 크기가 작아짐에 따라 비표면적이 급속히 커지기 때문에 입자가 유해 중금속 성분을 함유하고 있을 경우 그 중금속의 농축 정도가 크다. 지하철 역사는 사람들이 가장 많이 생활하는 지하 공간중의 하나이며, 유동인구가 많아 입자상 물질의 발생이 심한 지역으로 외기에 비해 희석, 화산 공간이 크지 않기 때문에 역사 내 유해 환경 오염 물질의 영향과 관리 대책에 대한 연구가 진행되고 있다. (중략)

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인위적 대형 배출원에서 SEM-EDS법을 이용한 개별 입자상 물질의 형태와 화학적 조성 분석 (Morphology and Chemical Composition Analysis of Individual Particles at Large Anthropogenic Emissions by SEM-EDS)

  • 양수명;박정호;정재우;서정민;최금찬
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2003년도 추계학술대회 논문집
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    • pp.368-369
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    • 2003
  • 각종 배출원에서 배출된 입자상 물질은 대기 중 확산, 이동, 침착 등을 통해 국지적 도시오염 뿐만 아니라 장거리까지도 이동함으로서 광역적 대기오염의 원인이 되고 있는 등 입자상 물질의 발생원 추적에 관한 연구가 필요한 실정이다. 지금까지 입자상 물질의 발생원 추적은 대부분 배출원의 발생량 조사나 필터에 포집된 시료의 전체적인 화학적 분석의 개념으로 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화되고 있다. (중략)

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가열되는 회전원판으로의 입자 침착 해석 (Analysis on Particle Deposition on a Heated Rotating Disk)

  • 유경훈
    • 대한기계학회논문집B
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    • 제26권2호
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    • pp.245-252
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    • 2002
  • Numerical analysis was conducted to characterize particle deposition on a horizontal rotating disk with thermophorectic effect under laminar flow field. The particle transport mechanisms considered were convection, Brownian diffusion, gravitational settling and thermophoresis. The averaged particle deposition velocities and their radial distributions for the upper surface of the disk were calculated from the particle concentration equation in a Eulerian frame of reference for rotating speeds of 0∼1000rpm and temperature differences of 0∼5K. It was observed from the numerical results that the rotation effect of disk increased the averaged deposition velocities, and enhanced the uniformity of local deposition velocities on the upper surface compared with those of the disk at rest. It was also shown that the heating of the disk with ΔT=5K decreased deposition velocity over a fairly broad range of particle sizes. Finally, an approximate deposition velocity model for the rotating disk was suggested. The comparison of the present numerical results with the results of the approximate model and the available experimental results showed relatively good agreement between them.

정전압에 따른 클린룸 벽체에서의 입자침착 특성 (Characteristics of Particle Deposition onto the Cleanroom Wall Panel with Electrostatic Voltages)

  • 노광철;손영태;김종준;오명도
    • 설비공학논문집
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    • 제18권12호
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    • pp.1033-1038
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    • 2006
  • We carried out the experiments on particle deposition onto the cleanroom wall panels. And then we investigated the particle deposition characteristic coefficients for electrostatic voltages and particle size. It was found that there is little difference in characteristics of the particle deposition between the steel panel and the anti-static coating panel. In case of that the particle size is under $1.0{\mu}m$, the particle deposition characteristic coefficient becomes larger as the electrostatic voltage induced to the cleanroom wall panel is increasing. Where in case of that the particle size is over $3.0{\mu}m$, the particle deposition characteristic coefficients do not show any differences with the electrostatic voltages. It is due to that the electrostatic force is the major particle transport mechanism for submicron particles, while the gravitational settling is the major particle transport mechanism for overmicron particles when the electro-static voltages are induced to the cleanroom wall panel.

GC/MSD에 의한 식물중 PCBs, BHCs의 동시 분석 방법 연구 (A Study on Analytical Method of PCBs, BHCs in Plants using GC/MSD)

  • 여현구;김희강;천만영;김태욱;최민규;선우영
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2000년도 추계학술대회 논문집
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    • pp.83-84
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    • 2000
  • 식물은 반휘발성유기화합물(Semivolatile organic compounds : 이하 SOCs)의 지구적인 순환과 먹이 연쇄에 있어서 중요한 역할을 한다. 또한 식물은 대기중 가스상 SOCs을 보유하고 입자상 SOCs를 제거하는 역할을 하기 때문에 대기를 정화하는데 중요한 기능을 한다(Lorber et al, 1993). SOCs 화합물 중 PCBs와 BHCs는 친지질성(lipophilic) 유기염소계 화합물로 식물의 뿌리를 통해서는 흡입되지 않고 대기중에서 식물잎의 표면에 존재하는 지질에 침착되므로 식물잎에 침착된 오염물질은 대기의 농도에 의존한다. (중략)

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