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Simulation of Various Baffle to Improve Settling Efficiency in Constructed Wetland using CFD

인공습지의 비용 효율적 초기 침강지 설계를 위한 최적 도류벽 구조 모의

  • Received : 2017.10.18
  • Accepted : 2017.11.02
  • Published : 2017.11.30

Abstract

In this study, the removal efficiency of the wetland in terms of particulate matter and dead water zone through the application of baffles in the sedimentation were simulated with the use of Computational Fluid Dynamics (CFD) to determine the design of a cost-effective constructed wetland. As a result, it was analyzed that the application of the baffle in the sedimentation tank affect the flow and sedimentation rate. Fine particles such as $2{\mu}m$ and $5{\mu}m$ showed high sedimentation rate when the baffles are installed horizontally. large particles such as $10{\mu}m$ and $20{\mu}m$ showed also high deposition rate when the baffles are installed vertically. In addition, the vertical baffles is considered to be more efficient than other baffle types in terms of maintenance since the particulate matter are concentrated in narrow areas. Therefore, it is considered that the selection of the most applicable type of baffle depends on the design purpose of the wetland to be constructed.

본 연구에서는 비용효율적인 인공습지의 설계를 위하여 초기 침강지 내 다양한 도류벽형태에 따른 인공습지의 사수역 및 입자상 물질의 제거효율을 전산유체역학(Computational Fluid Dynamics, CFD)을 통해 연구하였다. 그 결과, 초기 침강지에서 도류벽의 형태는 유입 유속에 영향을 미치며, 침전률에도 큰 영향을 미치는 것으로 분석되었다. $2{\mu}m$$5{\mu}m$와 같은 미세한 입자에서는 수평으로 설치한 도류벽에서 침전률이 높았으며, $10{\mu}m$$20{\mu}m$ 크기의 큰 입자는 수직형 도류벽에서도 높은 침전률을 나타내었다. 또한, 수직형 도류벽의 경우 좁은 면적에 침전이 집중적으로 이루어지기에 다른 형태에 비해 유지관리가 효율적일 것으로 판단되었다. 이에 인공습지의 설계 목적에 따라 가장 적절한 도류벽의 형태를 선정하여 설계해야 할 것으로 보여진다.

Keywords

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