• Title/Summary/Keyword: 임팩터

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Measurements of Diesel Particle Size Distribution Using an ELPI (ELPI를 이용한 디젤 입자상물질의 입경 분포 측정)

  • 김홍석;조규백;정용일;이상수;성낙원
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.75-76
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    • 2003
  • 본 연구는 ELPI(Electrical Low Pressure Impactor)를 이용하여 소형디젤기관에서 배출되는 입자상물질의 입경분포를 측정하였으며, 희석공기온도, 희석비, 측정위치가 측정에 미치는 영향을 고찰하였다. 본 연구에서는 배기량이 3000 cc인 간접분사식 소형디젤기관에서 발생하는 입자상물질의 입경분포를 고찰하고자 Dekati사의 ELPI를 사용하였다. 다단임팩터의 오염을 막기위해 ejector 형식의 2단 희석장치를 사용하였다.(중략)

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Performace of a Cyclone and an impactor Using Monodisperse and Polydisperse Particles (단분산 입자와 다분산 입자를 이용한 싸이클론 및 임팩터의 성능평가)

  • Im Gyeong-Su;Lee Gyu-Won
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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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)

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Evaluation of an electrical impactor with porous metal substrate (다공성 금속판을 이용한 전기적 임팩터의 평가)

  • Jeong Jeong-Seon;Gwon Sun-Park;Lee Gyu-Won
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.11a
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    • pp.276-277
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    • 2002
  • One of drawbacks of the inertial impactor measurement is the required long sampling time (Keskinen et al., 1992). In a gravimetric method, an impaction substrate must be weighed and placed on the corresponding collection plate before being assembled. After sampling, the inertial impactor is disassembled and the collection plate is weighted again. The sampling time depends on the sampled particle mass because the collected particle mass must be sufficiently high to be measured by a sensitive microbalance. (omitted)

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The effect of cooling an impaction plate on impactor performance (환경입자제어용 관성충돌기의 충돌판 냉각에 따른 효율곡선의 변화)

  • Lee, Byung-Uk;Kim, Sang-Soo
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.596-599
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    • 2001
  • Recently, as the environmental pollution becomes an important issue, aerosols which are the main components of the atmospheric pollution become the subject of a lot of researches. An impactor is a kind of sampling and measuring equipment for aerosols since 1970s. The impactor uses coating materials to obtain high performance. However, there are a lot of situations when coating materials are not available and in this case the classification efficiency of the impactor decreases significantly. In this study, the impaction plate of the impactor is cooled, therefore the impactor performs efficiently when coating materials are not available.

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Condensational Growth of Fine Aerosol Particles to Increase Precipitation Efficiency (집진효율 향상을 위한 미세 에어로졸 입자의 응축에 의한 성장 연구)

  • Han, Sang-Woo;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.8
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    • pp.1069-1076
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    • 2000
  • As the environmental problems grow, the regulation of the pollutants emitted from power plants increases. Most of the pollutants in particle phase are removed by particle removal facilities, but fine particles between 0.1 micron and I micron in diameter have a low removal efficiency compared to particles in other size ranges. Therefore the present concern has concentrated on the removal of those fine particles. The purpose of this study is to grow fine particles by condensation to the range larger than I micron. Theoretically the general dynamic equation is solved with an assumption that the particle size follows a log-normal distribution to calculate the temporal behavior of the size distribution. Experiments have been carried out to compare the results with the theoretical predictions. Particles grown by condensation are sampled by impactors and observed with SEM photographs.

Design and Performance Evaluation of a Faraday Cage and an Aerosol Charger (패러데이 케이지와 에어로졸 하전기의 설계 및 성능평가)

  • Ji, Jun-Ho;Bae, Kwi-Nam;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.3
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    • pp.315-323
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    • 2004
  • An electrical cascade impactor is a multi-stage impaction device to separate airborne particles into aerodynamic size classes using particle charging and electrical detection techniques. A Faraday cage and an aerosol charger, which are basic components of the electrical cascade impactor, were designed and evaluated in this study. The low-level current response of the Faraday cage was investigated with changing particle size and air flow rate by using sodium chloride (NaCl) particles. The response of the prototype Faraday cage was very similar to that of a commercial aerosol electrometer (TSI model 3068) within ${\pm}$5% for singly-charged particles. The response linearity of the prototype Faraday cage could be extended up to flow rate of 30 L/min. For the performance evaluation of the aerosol charger the monodisperse liquid dioctyl sebacate (DOS) particles, with diameters of 0.1∼0.8$\mu\textrm{m}$, were generated using spraying from an atomizer followed by evaporation-condensation process. Typical performance parameters of the aerosol charger such as P$.$n, wall loss, and elementary charges per particle were evaluated. The performance of the prototype aerosol charger was found to be close to that of the aerosol charger used in an electrical low pressure impactor (ELPI, Dekati).

Design and Performance Evaluation of a Diode Type Corona Charger for Real-Time Measurement of the Submicron Aerosol (실시간 미세입자 측정을 위한 다이오드형 코로나 하전기의 설계 및 성능평가)

  • Cho, Myung-Hoon;Ji, Jun-Ho;Park, Dong-Ho;Bae, Gwi-Nam;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.9
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    • pp.1066-1074
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    • 2004
  • With a diode corona charger, which is a component of ELPI(Electrical Low Pressure Impactor), aerosol particles are charged to make electrical detection possible before they are collected by the impactor. We designed and evaluated two cylindrical corona chargers, each of which had a central corona needle electrode. For the performance evaluation of each corona charger the polydisperse dioctyl sebacate(DOS) particles, with diameters of 0.1∼0.8 $\mu$m and NaCl particles, smaller than 0.1$\mu$m, were used. The particles were then led through an electrostatic classifier (TSI model 3081) to classify monodisperse aerosol with minimal size deviation. After evaluating the wall loss of the particles in the corona charger, we measured the product of penetration and number of charges, Pㆍn, to evaluate the corona charger efficiency at high positive voltages of 4, 5, 6 kV.

Collection Characteristics of a MOUDI Cascade Impactor for Coarse Particles (다단 임팩터(MOUDI)의 조대 입자 채취 특성)

  • 배귀남;지준호;문길주
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.6
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    • pp.799-804
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    • 1999
  • Particle collection characteristics of the MOUDI cascade impactor has been studied for coarse particles in the range of 2 to 20$mu extrm{m}$ in aerodynamic diameter. A vibrating orifice aerosol generator was empolyed to generate monodisperse test aerosols. The oleic acid and sodium chloride(NaCl) particles were used as test aerosols. Aluminum foil and Teflon filter were selected as impaction media. The sampling flow rate was changed from 25 to 35L/min. Particle collection efficiency for single stage was examined for liquid particles. The stage response was obtained experimentally for the cascade impactor composed of three stages and a backup filter. The results showed that most of particle collection efficiencies measured in this work are similar to the efficiency curves obtained by Marple et al.(1991). For particles less than cut-off size of the stage, the collection efficiencies of solid particles are similar to those of loquid particles. However, the collection efficiency of solid particles decreases with mereasing particle diameter for the particles greater than the actual cut-off size of the impactor. The particle collection efficiency increases with increasing sampling flow rate at the same particel size. However, the collection efficiency curves seem not to be greatly shifted with the flow rate. The stage responses obtained by direct measurements in this work are in good agreement with those derived from the collection efficiency curves for single stage.

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Numerical Simulation of Impactor Collection Efficiency according to Altitude (대기 고도에 따른 입자 포집용 관성 임팩터의 설계 및 포집효율 예측)

  • Kim, Gyuho;Yook, Se-Jin;Ahn, Kang-Ho
    • Particle and aerosol research
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    • v.8 no.1
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    • pp.1-8
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    • 2012
  • In this study, the collection efficiency of inertial impactors was numerically simulated by employing the statistical Lagrangian particle tracking(SLPT) model. The SLPT model was proven to be correct in predicting the impactor collection efficiency, when the numerically obtained collection efficiencies were compared with the experimental data of Marple et al.(1987) at normal pressure level and the experimental data of $Marjam{\ddot{a}}ki$ et al.(2000) at low pressure level. Based on the validation results, balloon-borne impactors with the cut-off sizes of $1{\mu}m$, $2.5{\mu}m$, and $10{\mu}m$ were designed. Then, the sampling flowrates of the inertial impactors, required to keep the cut-off sizes constant at different pressures and temperatures, were estimated according to the altitude.

Characterization of Chemical Composition and Size Distribution of Atmospheric Aerosols by Low-Pressure Impactor (저압 임팩터를 이용한 대기 에어로졸 입자의 입경분포 측정과 화학조성 자료의 해석)

  • 박정호;최금찬
    • Journal of Korean Society for Atmospheric Environment
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    • v.13 no.6
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    • pp.475-486
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    • 1997
  • The characteristics of atmospheric aerosols were investigated as a function of particle size and water solubility. The atmospheric aerosols were sampled with classifying into 12 size ranges by the use of Andersen low-pressure impactor. Collected aerosol particles were extracted by ultrapure water and filtered to be separated into water-soluble and insoluble components. The concentrations 12 elements in both components were determined by PIXE analysis. And the concentrations of 8 ions in the soluble component were analyzed by ion chromatography. In general, the mass size distribution of particulate matter was represented as a bimodal distribution. The mass size distributions of S$(SO_4^{2-}), K(K^+), Zn and NH_4^+$ skewed to the smaller size range and those of Si, Ca$(Ca^{2+}), Fe, Na^+ and Mg^{2+}$ skewed to the larger size range. They had roughly one peak in the fine and coarse particle region,respectively. On the other hand, the mass size distribution of Ti, Mn, Ni, Cu, $Cl^- and NO_3^-$ were represented as the bimodal distribution. Fe and Si in the aerosol particles extracted into pure water are existing in high insoluble state. Conversely, almost the whole of S is dissolved in water.

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