A 3-d Model for Oxygen Consumption in a River Using Computational Fluid Dynamics (cfd)

This work presents a three-dimensional Computational Fluid Dynamics (CFD) in house model to simulate the dispersion of organic substances along a river. The finite volume method is used to aproximate the conservation of momentum and mass equations. A Cartesian coordinate system has been chosen to represent the river. Turbulence is taken into account by a zero-order equation model. The Streeter-Phelps model has been used to predict the dissolved oxygen along the river. Results show that the proposed methodology is a good tool for the evaluation of the environmental impact caused for pollutants emissions in rivers. The in house software, developed from the model in Fortran language, is very fast, especially when compared to other commercial CFD packages. Experimental comparisons for soluble chloride dispersion have been made for the Atibaia-River near REPLAN-Paulínia (major petroleum refinery in Brazil). The results show good agreement with experimental data.