Lessons Learned from 10 years of Clarifier CFD Modeling - the 2Dc Experience

In WEFTEC 2005 McCorquodale et al. presented a paper describing the development of a public domain Computational Fluid Dynamics (CFD) model for the assessment, design and upgrading of primary and secondary circular clarifiers. The model, referred as 2Dc, was developed at the University of New Orleans and at that time represented the result of approximately 30 years of research and development. The model was developed with the financial support of the U.S. EPA and by 2005 had already been applied to projects in Canada, USA, Japan, Korea and Australia. The rectangular version of the 2Dc model (2Dr) was introduced by McCorquodale et al. in 2006. Today, the 2Dc/r models are used by many consultants around the world. The objectives of this paper is to present where we are after 10 years of application, what are the lessons learned, what are the model limitations and also to present a compilation of successful case studies which have led to clarifier optimization and maximization of plant peak flow capacity.