Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
권호 표지
DOI QR코드

DOI QR Code

Estimation of Settling Efficiency in Sedimentation Basin Using Particle Tracking Method

입자추적기법을 이용한 침전지의 효율 평가

  • 이길성 (서울대학교 지구환경시스템공학부) ;
  • 김상훈 (서울대학교 지구환경시스템공학부)
  • Published : 2004.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

Sedimentation basin plays an important role in urban water treatment, and there are many complicated phenomena which need to be understood for efficient design and control of it. Especially, the study on the improvement of settling efficiency is required. In this study, commercial CFD (Computational Fluid Dynamics) program, FLUENT, and particle tracking method were used to simulate the flow in sedimentation basin, and to predict the settling efficiency. Computational domain of real scale was made, and detail factors such as porous wall, and outlet trough were considered instead of being simplified. The simulation results were compared with the experimental data to calibrate the parameters of particle tracking method. Sensitivity analysis showed that the particle diameter had more significant effects on settling efficiency than the particle density. The computation results gave the best agreements with the experimental data, when the value of particle diameter was 26.5 ${\mu}{\textrm}{m}$.

침전지는 수처리 공정에서 중요한 조작 중 하나이며, 침전지내에서는 응집과 침전이 일어남에 따라 입자의 크기분포가 변하는 복잡한 현상이 발생한다. 따라서 침전지의 효율적인 설계나 운영을 위해서는 이러한 현상에 대해 이해해야만 하며, 침전효율의 극대화를 위한 연구가 필요하다. 본 연구에서는 침전지내의 흐름을 모의하기 위하여 범용 CFD 프로그램인 FLUENT를 이용하였으며, 침전효율을 평가하기 위하여 FLUENT에서 제공되는 입자추적기법을 사용하였다. 또한 침전지의 형상을 지나치게 단순화시키는 기존의 연구와는 달리 본 연구에서는 실제 현장에서 사용되는 규모와 침전지내 인자들 (유입부 정류벽, 유출부 트라프 등)이 수치모의에 최대한 반영되었으며, 현장실험의 결과를 바탕으로 민감도 분석을 수행해 수치모의에 사용되는 매개 변수들을 보정하였다. 민감도 분석 결과 입자의 직경이 입자의 밀도에 비해서 민감도가 큰 것으로 나타났고, 침전효율이 실헐결과와 가장 잘 일치할 때의 직경값을 결정해본 결과 입자의 직경값이 26.5 $\mu\textrm{m}$로 나타났다.

Keywords

References

  1. 노성진 (2001). CFD를 이용한 장방형 침전지내 흐름의 수치모의. 석사학위논문 서울대학교. p. 67-103
  2. Adbel-Gawad, S.M., and McCorquodale, J.A. (1984). 'Strip integral method applied to settling tanks.' Journal of Hydraulic Engineering, ASCE, Vol. 115, No. 1, pp. 1-17
  3. Adams, E.W., and Rodi, W. (1990). 'Modeling flow and mixing in sedimentation tanks.' Journal of Hydraulic Engineering, ASCE, Vol. 116, No. 7, pp. 895-913 https://doi.org/10.1061/(ASCE)0733-9429(1990)116:7(895)
  4. Brouckaert, C.J., and Buckley, C.A., (1999). The use of computational fluid dynamics for improving the design and operation of water and wastewater treatment plants.' Water Science and Technology, Vol. 40, No. 4-5, pp. 81-89 https://doi.org/10.1016/S0273-1223(99)00488-6
  5. Deininger, A., Holthausen, E., and Wilderer, P.A. (1998). 'Velocity and solids distribution in circular secondary clarifiers: Full scale measurements and numerical modeling.' Water Science and Technology, Vol. 32, No. 10, pp. 2951-2958 https://doi.org/10.1016/S0043-1354(98)00072-4
  6. DeVantier, B.A., and Larock, B.E. (1987). 'Modeling sediment-induced density current in sedimentation basins.' Journal of Hydraulic Engineering, ASCE, Vol. 113, No. 1, pp. 80-94 https://doi.org/10.1061/(ASCE)0733-9429(1987)113:1(80)
  7. FLUENT5 user's guide. (1998). Fluent Inc.
  8. Imam, E., McCorquodale, J.A., and Bewtra, J.K. (1983). 'Numerical modelling of sedimentation tanks.' Journal of Hydraulic Engineering, ASCE, Vol. 109, No. 12, pp. 1740-1754 https://doi.org/10.1061/(ASCE)0733-9429(1983)109:12(1740)
  9. Krebs, P., Stamou, A I., Garcia-Heras, J.L., and Rodi, W. (1996). 'Influence of inlet and outlet configuration on the flow in secondary clarifiers.' Water Science and Technology, Vol. 34, No. 5-6, pp. 1-9 https://doi.org/10.1016/0273-1223(96)00622-1
  10. LeVeque, R.J. (1990). Numerical methods for conservation laws, Birkhauser
  11. Schamber, D.R., and Larock, B.E. (1981). 'Numerical analysis of flow in sedimentation basins.' Journal of Hydraulic Division, ASCE, Vol. 107, No. 5, pp. 575-591
  12. Stamou, A.I., Adams, E.W., and Rodi, W. (1989). 'Numerical modelling of flow and settling in primary rectangular clarifier.' Journal of Hydraulic Research, Vol. 27, No. 5, pp. 665-682 https://doi.org/10.1080/00221688909499117
  13. Stovin, V.R., and Saul, A.J., (1996). 'Efficiency prediction for storage chambers using computational fluid dynamics.' Water Science and Technology, Vol. 33, No. 9, pp. 163-170 https://doi.org/10.1016/0273-1223(96)00383-6
  14. Stovin, V.R., and Saul, A.J. (1998). 'A computational fluid dynamics(CFD) particle tracking approach to efficiency prediction.' Water Science and Technology, Vol. 37, No. 1, pp. 285-293 https://doi.org/10.1016/S0273-1223(97)00780-4
  15. Stovin, V.R., and Saul, A.J. (1999). 'Field testing CFD-based predictions of storage chamber gross solids separation efficiency.' Water Science and Technology, Vol. 39, No. 9, pp. 161-168 https://doi.org/10.1016/S0273-1223(99)00229-2
  16. Yoon, T.H., and Lee, S.O. (2000). 'Numerical modeling of sedimentation basins with a baffle.' Journal of Civil Engineering, KSCE, Vol. 4, No. 4, pp. 227-232

Cited by

  1. Three-dimensional numerical modeling of sediment-induced density currents in a sedimentation basin vol.27, pp.3, 2013, https://doi.org/10.11001/jksww.2013.27.3.383