Bacterial Regrowth Model for Water Distribution Systems Incorporating Alternating Split-Operator Solution Technique

Abstract

This paper presents a new mathematical model of bacterial regrowth in distribution systems, which combines hydraulic calculations, inclusive of dispersion, with a description of the following microbial processes: free and attached growth, detachment, endogenous respiration, and inactivation by chlorine. The microbial process description has been simplified from previous models based on a sensitivity analysis. The alternating split-operator algorithm is used to solve this model. This method differs from previous approaches by decoupling the transport and reaction processes, allowing a choice among numerical algorithms that is best suited for each part of the model. The proposed solution resolves sharp fronts of a concentration profile more accurately than traditional finite difference methods. The results of the model are also compared against