A NONORTHOGONAL CURVILINEAR SYSTEMS-MODEL OF SPECIES TRANSPORT IN SHALLOW FLOW DOMAINS

This paper is concerned with curvilinear systems modelling of pollutant transport in shallow flow domains, such as rivers, lakes and reservoirs. Prediction of the flow hydrodynamics is based on a finite difference solution of the depth-averaged Reynolds equations expressed as non-orthogonal boundary-fitted depth-averaged stream function and vorticity transport equations. Once the flow kinematics are established, the velocity field is used to drive the pollutant transport by means of a transformed depth-averaged species equation, where it is assumed that the pollutant is well mixed over the depth. Validation is carried out against analytical solutions for pure advection and pure diffusion, as well as experimental data from a circular reservoir in which the spread of dye is monitored by video camera.