Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Analysis of Fluid Flows in a Stirred Tank Using Computational Fluid Dynamics

전산유체역학을 이용한 교반탱크 내 유체흐름 해석

  • Kim, Mi Jin (Department of Chemical Engineering, Kongju National University) ;
  • Lee, Kyung Mi (Department of Chemical Engineering, Kongju National University) ;
  • Park, Kyun Young (Department of Chemical Engineering, Kongju National University)
  • 김미진 (공주대학교 화학공학부) ;
  • 이경미 (공주대학교 화학공학부) ;
  • 박균영 (공주대학교 화학공학부)
  • Received : 2010.01.15
  • Accepted : 2010.03.10
  • Published : 2010.06.30
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Abstract

The flow patterns in a stirred tank, 1m in diameter and 1 m in height, were studied using CFX, a commercial computational fluid dynamics program, with the impeller rotation speed, the impeller blade angle and the tank-bottom shape varied and the baffles included or excluded. A vortex was observed in the center of the tank in the absence of the baffles, and the intensity of the vortex increased with increasing the rotation speed. The vortex was considerably reduced in the presence of the baffles. An increase in the blade angle increased the vertical flow and decreased the vortex intensity. The flow in the corners of the tank bottom turned smoother as the tank bottom was varied in shape from flat to round.

직경 1 m, 높이 1 m의 교반탱크 내 유체흐름 패턴을 상용 전산유체역학 프로그램의 하나인 CFX를 사용하여 해석함으로써 교반속도, 임펠러 회전날개의 경사각, 방해판의 존재 유무, 탱크바닥 형태가 흐름패턴에 미치는 영향을 알아보았다. 방해판이 없을 경우 탱크 중심에서 와류가 관찰되었으며 교반속도가 증가함에 따라 탱크 중심의 와류 현상이 증가하였으나, 방해판 설치에 의해 와류가 감소하였다. 임펠러 날개의 경사각을 증가시킴으로써 교반탱크 상하로의 유체흐름이 증가하였고 와류도 감소하였다. 탱크바닥을 수평으로 하는 것 보다 둥글게 함으로써 탱크 바닥 구석에서 유체흐름이 원활하게 변화하였다.

Keywords

References

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