CFD Hydraulic Design Methods for Water Disinfection Systems

MMI Engineering have developed new hydraulic design manuals for drinking water disinfection equipment for United Utilities plc. These have been developed in response to a number of investigations of contact tanks, service reservoirs and pipe loops using Computational Fluid Dynamics (CFD) where the flow conditions did not provide the expected hydraulic efficiencies. Data generated from multiple CFD analyses were used to determine the geometric features which affect hydraulic efficiency; and hand calculation methods were devised from the CFD data to provide accurate assessment of hydraulic efficiency for both service reservoirs and pipe loops. The novelty in this work has been the extensive use of CFD, removing the need for traditional physical models, dye-trace experiments, etc, which can be time consuming and expensive. The work has not only shown that existing design assumptions were over-optimistic in estimating hydraulic efficiency, but has also provided new methods of calculating this efficiency and encapsulated this in easy to use design guides.