USE OF COMPUTATIONAL FLUID DYNAMICS TECHNIQUE TO INSTRUMENT CSOs

摘要

The assessment of the flows and the pollutant load discharged into the natural environment requires the installation of an adequate instrumentation. The knowledge of the hydraulic operation of the Combined Sewer Overflows (CSOs) is thus essential. We use 3D modeling (FLUENT~R) in order to understand the hydrodynamic behavior of complex CSOs. Initially, the numerical results arising from 3D modeling of the flows in side storm overflows were validated using the experimental data of the "CSO" pilot. In the second time, we applied the 3D modeling to the CSO on real site (in France) that was instrumented with sensors. Careful consideration was given to the boundary condition at the downstream of the work. Simulations enabled us to know the various shapes of water lines and the evolution of velocity field. The location of the free surface was done by means of Volume Of Fluid (VOF) method. The k-e model is used for the turbulence. The analysis of the results of 3D simulation was enabled to propose the locations of sensors in order to improve the instrumentation of this CSO for flow measurement.