Relationship between ICAC EP-7 and %RMS, Standards for Gas Flow Uniformity inside Electrostatic Precipitators

전기집진기 내부 유동 균일도 평가 기준인 ICAC EP-7과 %RMS 간 상관관계

  • Shin, Wan-Ho (Environmental and Energy System Research Division, Korea Institute of Machinery and Materials) ;
  • Hong, Won-Seok (Environmental and Energy System Research Division, Korea Institute of Machinery and Materials) ;
  • Song, Dong-Keun (Environmental and Energy System Research Division, Korea Institute of Machinery and Materials)
  • 신완호 (한국기계연구원 그린환경에너지기계연구본부) ;
  • 홍원석 (한국기계연구원 그린환경에너지기계연구본부) ;
  • 송동근 (한국기계연구원 그린환경에너지기계연구본부)
  • Received : 2009.12.09
  • Accepted : 2010.03.02
  • Published : 2010.04.30


Gas flow uniformity is an important factor to guarantee particle removal performance of electrostatic precipitators (EP), and the gas flow uniformity is evaluated by a fraction of standard deviation to the mean of gas flow distribution (%RMS) or a technical standard, ICAC EP-7, provided by The Institute of Clean Air Companies. In this study, relationship between the ICAC EP-7 and %RMS in evaluation of gas flow uniformity was investigated in terms of flow velocity. The maximum values of %RMS for gas velocity distribution of normal distribution has been obtained, and the maximum values of %RMS with gas velocity distribution satisfying ICAC EP-7 standards were also evaluated. With gas flow distribution obtained from CFD analysis and physical model test of real EP, %RMS values were calculated and it was tested if those gas flow distribution satisfy the criteria specified in ICAC EP-7. The %RMS values satisfying criteria of ICAC have been appeared to have similar values with %RMS values calculated with normal distribution of gas velocities.


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