UCLA

Computational fluid mechanics were used to determine the optimal depth of a skirt baffle in a circular-type secondary clarifier. Three sets of simulations were performed. The first, set A, determined the better range of operation conditions; set B investigated the numerical stability of the simulations and served as a base for simulation and set C which analyzed the skirt baffle depth on the effluent suspended solids, recycle solids concentration and biosolids mass in the clarifier. The skirt baffle depth was evaluated for three sets of surface overflow conditions and ranged from 10% to 90% of the clarifier depth. Best clarifier performance occurred when the skirt baffle depth was approximately 70% of the clarifier depth. The analysis used Fluent� log files to create a less time-consuming approach for clarifier analysis.