Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Study on Flow Characteristics and Classification Performance of Circulating Air Classifier

수치해석을 이용한 순환형공기분급기 유동특성 및 분급성능 연구

  • 윤정환 (대구대학교 기계공학부) ;
  • 정준교 (현대건설(주) 연구개발본부)
  • Received : 2016.08.09
  • Accepted : 2017.01.14
  • Published : 2017.03.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, we performed numerical simulations on a circulating air classifier using a commercial computational fluid dynamics program. The variations in the grade efficiency, the cut-size and the cut-sharpness were calculated and discussed. By controlling the rotating speed of the main fan, the cut-size could be rapidly increased. However the linearity of the cut-size variation with respect to the main fan speed was not sufficient for application to contaminated soil classification processes. On the other hand, by varying the rotating speed of the classifying fan, the cut-size gradually decreased and could be precisely adjusted. Using both the main fan and the classifying fan, we could achieve larger cut-sharpness values and better classifying performances.

본 연구에서는 전산유체역학 프로그램을 이용하여 순환형공기분급기 내부유동 및 입자거동을 해석하였다. 주날개 및 분급날개의 회전속도 조건을 변화시키며 이에 따른 등급분급효율, 절단입경 및 분급첨예도 변화를 예측하였다. 주날개의 회전속도를 제어함으로써, 절단입경을 증가시킬 수 있었으나, 오염토양 분급에 적용할 수 있을 정도의 정확도를 확보할 수 없었다. 반면, 분급날개의 회전속도를 증가시킴으로써, 절단입경을 감소시킬 수 있었으며, 보다 정확하게 입자를 선별할 수 있었다. 결과적으로 주날개와 분급날개를 동시에 사용할 경우, 높은 분급첨예도 결과를 보이며, 우수한 분급특성을 유지할 수 있었다.

Keywords

References

  1. Yoon, J. H., Cheong, J. G., Kang, W. H., Kim, K. and Chae, H., 2015, "Applications of the Dry Disposal Process in the Arsenic Contaminated Soil Treatment," ICOSSE 2015, Balatonfured, Hungary.
  2. Hosokawa Alpine, 2009, Powder and Particle Processing, Hosokawa Alpine, Augusburg, pp. 4-24.
  3. Ko, H. K. and Kim, H. S., 2013, "Theoretical Analysis and Experimental Evaluation of Small Cyclone Separator to Remove Fine Particulate Matter," Trans. Korean Soc. Mech. Eng. B, Vol. 37, No. 1, pp. 77-82. https://doi.org/10.3795/KSME-A.2013.37.1.077
  4. Shapiro, M. and Galperin, V., 2005, "Air Classification of Solid Particles: a Review," Chem. Eng. and Process., Vol. 44, pp. 279-285. https://doi.org/10.1016/j.cep.2004.02.022
  5. Gao, L., Yu, Y. and Liu, J., 2013, "Study on the Cut Size of a Turbo Air Classifier," Powder Technology, Vol. 237, pp. 520-528. https://doi.org/10.1016/j.powtec.2012.12.043
  6. Feng, Y., Liu, J. and Liu, S., 2008, "Effects of Operating Parameters on Flow Field in a Turbo Air Classifier," Mineral Engineering, Vol. 21, pp. 598-604. https://doi.org/10.1016/j.mineng.2007.11.008
  7. Eswaraiah, C., Angadi, S. I. and Mishra, B. K., 2012, "Mechanism of Particle Separation and Analysis of Fish-hook Phenomenon in a Circulating Air Classifier," Powder Technology, Vol. 218, pp. 57-63. https://doi.org/10.1016/j.powtec.2011.11.036
  8. Johansson, R. and Evertsson, M., 2012, "CFD Simulation of a Gravitational Air Classifier," Mineral Engineering, Vol. 33, pp. 20-26. https://doi.org/10.1016/j.mineng.2012.01.007
  9. Johansson, R. and Evertsson, M., 2014, "CFD Simulation of a Centrifugal Air Classifier used in the Aggregate Industry," Mineral Engineering, Vol. 63, pp. 149-156. https://doi.org/10.1016/j.mineng.2014.03.013
  10. Ansys Inc., 2015, Ansys CFX-Solver Theory Guide, Ansys Inc., Canonsburg, pp. 317-319.
  11. Misiulia, D., Andersson, A. G. and Lundstrom, T. S., 2015, "Effects of the Inlet Angle on the Flow Pattern and Pressure Drop of a Cyclone with Helical-roof Inlet," Chem. Eng. Technol., Vol. 102, pp. 307-321.
  12. Malvern Instruments Worldwide, 2012, A Basic Guide to Particle Characterization, Malvern Instruments Limited, Worcestershire, pp. 1-26.