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

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Study on Flow Characteristics of Hollow Fiber Membrane Module for Water Recovery Cooling Tower

수분회수 냉각탑에 적용되는 중공사막 모듈의 유동특성에 관한 수치해석적 연구

  • Park, Sang Cheol (Dept. of Mechanical Engineering, Chungnam Nat'l Univ.) ;
  • Park, Hyun Seol (Climate Change Technology Research Division, Korea Institute of Energy Research) ;
  • Lee, Hyung Keun (Climate Change Technology Research Division, Korea Institute of Energy Research) ;
  • Shin, Weon Gyu (Dept. of Mechanical Engineering, Chungnam Nat'l Univ.)
  • Received : 2017.02.13
  • Accepted : 2017.05.23
  • Published : 2017.08.01
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Abstract

The purpose of this study is to analyze the flow characteristics when a staggered hollow fiber membrane module is modeled as a porous medium. The pressure-velocity equation was used for modeling the porous medium, using pressure drop data. In terms of flow characteristics, we compared the case of the "porous medium" when the membrane module was modeled as a porous medium with the case of the "membrane module" when considering the original shape of the membrane module. The difference in pressure drop between the "porous medium" and "membrane module" was less than 0.6%. However, the maximum flow velocity and mean turbulent kinetic energy of the "porous medium" were 2.5 and 95 times larger than those of the "membrane module," respectively. Our results indicate that modeling the hollow fiber module as a porous medium is useful for predicting pressure drop, but not sufficient for predicting the maximum flow velocity and mean turbulent kinetic energy.

본 연구의 목적은 수분회수 냉각탑에 설치된 엇갈림(staggered) 형태로 배치된 중공사막 모듈을 다공성 매질(porous medium)로 모델링 시 유동특성을 수치 해석적으로 검토하는 것이다. 1단으로 설치된 중공사막 모듈의 차압 데이터를 이용하여 다공성 매질의 모델링을 위한 압력-속도 2차 식을 도출하였다. 중공사막 모듈을 다공성 매질로 모델링한 경우 ("다공성 매질")와 중공사막 모듈의 형상을 그대로 고려한 경우 ("멤브레인 모듈")에 대해 유동 특성을 비교하였다. "다공성 매질"의 경우 "멤브레인 모듈"에 비해 유동에 의한 압력 변화는 0.6 % 미만의 적은 차이를 나타냈으나, 최대 유속은 약 2.5배, 평균 난류 운동에너지는 95배로 크게 나타났다. 이를 통해 다공성 매질로의 모델링은 압력강하는 잘 구현하나, 유속 및 난류 운동에너지는 잘 모사하지 못함을 알 수 있었다.

Keywords

References

  1. Seo, S. H. and Sung, S. K., 2007, "Effect of Fouling Mitigation for Ceramic Ball in Cooling Water System of Heat Exchanger," Trans. Korean Soc. Mech. Eng. B, Vol. 31, No. 4, pp. 330-334. https://doi.org/10.3795/KSME-B.2007.31.4.330
  2. Jung, J.H., Jung, J.H. and Choi, Y. K., 2014, "Program Development for the Prediction of Cooling Tower Performance," Korean Journal of Air-Conditioning and Refrigeration Engineering, Vol. 26, No. 3, pp. 130-136. https://doi.org/10.6110/KJACR.2014.26.3.130
  3. Park, Y. C., 2010, "Vibration Analysis of a Cooling Fan Gear Reducer of the Secondary Cooling Tower in HANARO," Trans. Korean Soc. Mech. Eng. A, Vol. 34, No. 7, pp. 935-941. https://doi.org/10.3795/KSME-A.2010.34.7.935
  4. Kim, B. J. and Choi, Y. K., 2003, "A Numerical Study on the Performance Analysis of Plume Abatement Cooling Tower with Dry Type Heat Exchanger," Korean Journal of Air-Conditioning and Refrigeration Engineering, Vol. 15, No. 12, pp. 1018-1028.
  5. Choi, C. K., Choi, Y. K. and So, H. Y., 2001, "A Numerical Study on the Performance Analysis of the Plume Abatement NWD Cooling Tower," Korean Journal of Air-Conditioning and Refrigeration Engineering, Vol. 13, No. 11, pp. 1049-1059.
  6. Su, M. D., Tang, G. F. and Fu, S., 1999, "Numerical Simulation of Fluid Flow and Thermal Performance of a Dry-cooling Tower under Cross Wind Condition," Journal of Wind Engineering and Industrial Aerodynamics, Vol. 79, No. 3, pp. 289-306. https://doi.org/10.1016/S0167-6105(98)00121-4
  7. Kim, B. J. and Choi, Y. K., 2003, "A Numerical Study on the Performance Analysis of Plume Abatement Cooling Tower with Dry Type Heat Exchanger," Korean Journal of Air-Conditioning and Refrigeration Engineering, Vol. 15, No. 12, pp. 1018-1028.
  8. Kim, B. J. and Choi, Y. K., 2005, "Numerical Study on the Performance Analysis of Plume Abatement Cooling Tower with Dry Type Heat Exchanger," International Journal of Air-Conditioning and Refrigeration, Vol. 13, No. 2, pp. 61-70.
  9. Michioka, T., Sato, A., Kanzaki, T. and Sada, K., 2007, "Wind Tunnel Experiment for Predicting a Visible Plume Region from a Wet Cooling Tower," Journal of Wind Engineering and Industrial Aerodynamics, Vol. 95, pp. 741-754. https://doi.org/10.1016/j.jweia.2007.01.005
  10. Bouzereau, E., Genon, L. M. and Carissimo, B., 2008, "Application of a Semi-spectral Cloud Water Parameterization to Cooling Tower Plumes Simulations," Atmospheric Research, Vol. 90, pp. 87-90.
  11. Al-Waked, R., 2010, "Crosswinds Effect on the Performance of Natural Draft Wet Cooling Towers," International Journal of Thermal Sciences, Vol. 49, pp. 218-224. https://doi.org/10.1016/j.ijthermalsci.2009.07.012
  12. Tyagi, S. K., Pandey, A. K., Pant, P. C. and Tyagi, V. V., 2012, "Formation, Potential and Abatement of Plume from Wet Cooling Towers: A Review," Renewable and Sustainable Energy Reviews, Vol. 16, pp. 3409-3429. https://doi.org/10.1016/j.rser.2012.01.059
  13. Versteeg, H. K. and Malalasekera, W., 1995, "An Introduction to Computational Fluid Dynamics: the Finite Volume Method," 1st ed., LONGMAN, London, pp. 10-39.
  14. Kimura, I., and Hosoda, T., 2003, "A Nonlinear k-${\varepsilon}$ Model with Realizability for Prediction of Flows Around Bluff Bodies," International Journal for Numerical Methods in Fluids, Vol. 42, No. 8, pp. 813-837. https://doi.org/10.1002/fld.540
  15. FLUENT, ANSYS., 2015, "15.0 User Guide.", Release 14.
  16. Anqi, A. E., Alkhamis, N. and Oztekin, A., 2016, "Steady Three Dimensional Flow and Mass Transfer Analyses for Brackish Water Desalination by Reverse Osmosis Membranes," International Journal of Heat and Mass Transfer, Vol. 101, pp. 399-411. https://doi.org/10.1016/j.ijheatmasstransfer.2016.05.102