Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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CFD Simulation of the Effects of Inlet Flow rate on Hydraulic Behavior in Continuous Stirred-Tank Reactor (CSTR)

CFD 모사 기법을 이용한 유입 유량에 의한 연속 완전혼화 반응조 수리거동 고찰에 관한 연구

  • Lee, Young Joo (K-water Institute) ;
  • Oh, Jeong Ik (LH Institute) ;
  • Yoon, Sukmin (Division of Architectural, Urban and Civil Engineering and Engineering Research Institute, Gyeongsang National University) ;
  • Kim, Jong-Oh (Division of Architectural, Urban and Civil Engineering and Engineering Research Institute, Gyeongsang National University) ;
  • Park, No-Suk (Division of Architectural, Urban and Civil Engineering and Engineering Research Institute, Gyeongsang National University)
  • 이영주 (K-water 연구원 상하수도연구소) ;
  • 오정익 (LH 연구원) ;
  • 윤석민 (경상대학교 건축도시토목공학부 및 공학연구원) ;
  • 김종오 (경상대학교 건축도시토목공학부 및 공학연구원) ;
  • 박노석 (경상대학교 건축도시토목공학부 및 공학연구원)
  • Received : 2016.01.12
  • Accepted : 2016.01.25
  • Published : 2016.01.31
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Abstract

This paper describes three-dimensional computational fluid dynamics (CFD) simulation of liquid-liquid flow and transient tracer tests in a full-scale continuous stirred-tank reactor (CSTR) used for drinking water treatment. To evaluate the effects of inlet flow rate on hydrodynamic behavior in the selected CSTR, inlet flow rate was changed from 10% to 100% of the design flow rate. From the results of CFD simulation and analysis, as the inlet flow rate increases, Modal index and ${\beta}$ value are increased. Also, Morrill index shows local minimal points in relation to the inlet flow rate, which are observed at 20% and 40% of the design flow. As inlet flow Increases more than 40%, it is shown that Morrill index re-increases to close to ideal CSTR.

본 연구에서는 수처리 공정에 적용하고 있는 CSTR 반응조를 대상으로 유입 유량이 다양하게 변동하는 경우 반응조 내부 수리 거동을 조사하고자 하였다. 유입 유량의 변동은 설계 유량 대비 10~100%까지 변화시켰으며, 각 경우를 CFD 기법을 이용하여 transient 상태의 추적자 실험을 모의하였으며, 모사 결과로부터 2차 정보를 추출하여 수리 거동 지표를 계산하여 유입 유량과 수리거동의 관계를 면밀히 조사하였다. 그 결과, 유입 유량이 증가할수록 Modal index와 ${\beta}$값이 증가하는 거동을 보였으며 Morrill index는 유입 유량과의 관계에서 국부적인 극소값을 가지는 유입 유량이 두 곳 나타났는데 각각 설계 유량의 20%되는 지점과 40%가 되는 지점이었다. 두 극소값이 나타나는 유입 유량보다 유량이 증가하면 다시 Morrill index가 증가하는 현상을 보여 이상적인 CSTR 반응조에 근접하는 것으로 나타났다.

Keywords

References

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