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Optimization of influent and effluent baffle configuration of circular secondary clarifier using CFD and PIV test

CFD와 PIV test를 통한 원형 2차침전지 유입 및 유출배플 형상 최적화

  • Received : 2014.01.23
  • Accepted : 2014.02.12
  • Published : 2014.02.15

Abstract

One-dimensional flux theory (1DFT) is conventionally used for design of secondary clarifier of wastewater treatment plant. However, the 1DFT cannot describe turbulence, density current, shape parameters of the clarifier. In this study, we optimized the configurations of influent guide baffle and effluent baffle through the simulation using computational fluid dynamics (CFD) and its verification by particle image velocity (PIV) test. The energy dissipating inlet (EDI) without influent guide baffle ($0^{\circ}$) showed the best efficiency for minimizing downward velocity under the center well of the clarifier. The lowest velocity distribution around the effluent weir region could be obtained with the McKinney baffle (EB-2). The performances of the influent and effluent baffles were clearly verified by PIV test results.

Keywords

References

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