Journal of Korean Society of Water and Wastewater (상하수도학회지)

The Korean Society of Water and Wastewater (대한상하수도학회)
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Optimization of influent and effluent baffle configuration of a rectangular secondary clarifier using CFD and PIV test

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

  • Received : 2009.11.30
  • Accepted : 2010.02.05
  • Published : 2010.02.15
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Abstract

The influent and effluent baffle configurations seriously affect the hydraulic characteristics of the secondary clarifier in wastewater treatment plant. In this study, those baffle configurations were optimized by computational fluid dynamics(CFD) analysis and particle image velocity(PIV) test in order to obtain uniform flow in inlet region and to minimize upflow velocity in outlet region of the secondary clarifier. Theoretical analysis using CFD showed that more uniform flow could be accomplished when the influent baffle was located closely to the inlet opening. Effects of effluent baffle configuration on the upflow velocity in the outlet region of the secondary clarifier were analyzed with four types of effluent baffles which are widely adopted for secondary clarifier design. From the CFD analysis, McKinney baffle(EB-2) was estimated to be the most effective for restraining the upflow velocity in the outlet region and these trends were identified by PIV tests. In addition, the McKinney baffle showed the most uniform overflow velocity distribution around the weir.

Keywords

References

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