Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Characteristic of flow pattern and Particle Suspension in a Bottom Baffled Agitated Vessel

교반조 바닥의 방해판이 유동특성 및 입자부유에 미치는 특성

  • Lee, Young-Sei (School of Nano & Materials Science and Engineering, Kyungpook National University)
  • 이영세 (경북대학교 나노소재공학부)
  • Received : 2014.09.04
  • Accepted : 2015.02.12
  • Published : 2015.02.28
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Abstract

This study examined experimentally the characteristics of the flow pattern and particle suspension in an agitated vessel with a bottom baffle. A flow pattern of the particles was shown to increase the upward flow from the center of the agitated vessel bottom. The suspended particles from the experiment found that the particle suspension was promoted by the development of an Ekman boundary layer. The optimal conditions of the impeller, and the agitated vessel bottom baffle within the experimental range were as follows: Impeller, $n_p=6$, d/D=0.5, and b/d=0.3; and bottom baffle, $n_b=6$, $d_b/D=0.5$ and $b_w/D=0.05$.

교반조 바닥에 방해판이 부착된 경우 유동특성 및 입자부유특성을 실험적으로 연구하였다. 입자의 유동상태는 교반조 바닥 중심으로부터 상승류가 증가하였다. 입자부유 실험으로부터 에크만 경계층의 발달에 의해 입자부유가 촉진됨을 알았다. 본 실험범위 내에서의 임펠러 및 교반조 바닥 방해판의 최적조건을 다음과 같이 나타내었다. 교반임펠러 최적조건 : $n_p=6$, d/D=0.5, b/d=0.3, 교반조 바닥 방해판 최적조건 ; $n_b=6$, $d_b/D=0.5$, $b_w/D=0.05$.

Keywords

References

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