Flow Dynamics using CFD in Storage Tanks
Exact Sciences and Engineering
Civil and Mining Engineering
Drinking water storage tanks are essential components of the network supply system, either to balance the pressure on the network or to guarantee emergency reserves in case of a fire. The storage tanks are operated to meet the daily demands of the distribution network.
However, storage tanks are frequently referred as spots of quality degradation, mainly related to the design of the storage tanks that do not take into account the needed mixing and water renewal. The storage tanks design generates "dead zones", and these are responsible for the poor mixing and an extended Residence Time Distribution (RTD). An extended Residence Time Distribution combined with differential temperatures between the incoming water (inflow) and the stored water result in thermal stratification, causing zonal chlorine decay, biofilm development, sediment build-up.
It aggravated the formation of potentially carcinogenic toxic disinfection by-products, leading to an increase in the consumption of chlorine. For these reasons, there is an urgent need to understand the hydrodynamics in tanks, regarding their design/geometry, configuration and operational conditions in order to improve mixing conditions.
Contacts:
Nuno Martins
email: nunomiguelmartins@tecnico.ulisboa.pt
Department of Civil Engineering, Architecture and Georesources
