Dispersion of Pollutants in a River According to Its Geometry and Tributaries: A Case Study for River Paraiba do Sul—State of Sao Paulo, Brazil

摘要

This article aims to demonstrate how the dispersion of pollution is affected when the main flow of river changes due to river geometry also with inflows coming from tributaries. The river chosen is Paraiba do Sul because it flows through two important states in Brazil, Rio de Janeiro and Sao Paulo, and supplies water for several purposes, such as agriculture, drinking, energy, dissolution of domestic sewage, fishing, and so on. Through a single two-dimensional numerical simulation (Computational Fluid Mechanics—CFD) by commercial software COMSOL Multiphysics, it was possible to demonstrate how geometry of a river and tributaries' inflow rates changes the dispersion of pollutants along its course.