Author(s): Antonio Lastra; Alejandro Pinilla; Monica Ortega; Jaime Botello; Celia Ortega
Keywords: Water quality; CFD models; Drinking Water Tanks (DWT); Water flow
Abstract: Canal de Isabel II operates a total of 463 drinking supply tanks with a total storage capacity of 3,700,000 m3. In order of meeting water supply demands, these tanks must also guarantee the required water quality of water supply. The objective of this study has been to analyse the behaviour of water flow inside the drinking water tanks to improve water quality; the behaviour of the internal flow of more than 40 drinking water tanks has been characterised by means of 3D hydraulic modelling. CFD in a total of 120 simulations. It was observed that there is a heterogeneous distribution of the flow and, consequently, a high presence of very low velocity zones. In addition, short circuits, recirculation, and preferential paths were identified and quantified. Furthermore, reduced 3D models were simulated to quantify the effect of small design variations in the tanks (typology of columns, shape, turns, etc. ), with the aim of parametrisation design criteria. Considering the results of these models, constructive improvements have been implemented in the existing drinking water tanks, and potential design proposals for new tanks to be built. Finally, results evaluation, streamlines, and velocity isosurfaces were statistically analysed to decide the most geometrically efficient alternative for each tank, applying our own methodology with the aim of solving drinking water tank problematics. This was carried out at a further developmental stage of this project.