SIMULATION OF POLLUTANT TRANSPORT RESPONSES TO LOADING AND WEATHER VARIATIONS IN LAKE ST. CLAIR AND THE CONNECTING CHANNELS.

摘要

This dissertation presents a mathematical modelling framework which can be used to simulate the transport of toxic and conventional substances in surface waters for the Huron-Erie corridor of the Great Lakes. In simulating the transport of conventional pollutants in the rivers, a simple hydrodynamic submodel, which includes flow around islands, diversions and confluences, is used to establish the velocity fields. Then a stream function form of the transport equation is coupled with the k-(epsilon) equations in order to obtain the turbulent dispersion coefficients. The submodel uses a variable grid finite difference scheme. Once the velocity fields and dispersion coefficients have been obtained, the EPA (TOXIWASP) model is used to simulate the interaction between sediments and contaminants. In an attempt to include the effects of the seasonal variations on the circulation patterns in Lake St. Clair, a three dimensional finite element model which includes wind stress, bottom friction, Coriolis force, inflow, outflow and the bottom topography of the lake was developed and verified with field data. The overall root mean square differences between predicted and measured current magnitudes and directions were 1.3 cm.s(u27-1) and 22.5(DEGREES), respectively, whereas the correlation coefficients were 0.99 and 0.95, respectively. The Hydrodynamic submodel was tested for stability, convergence, and sensitivity to parameters such as wind shear, wind direction, slip-coefficient for bottom friction and vertical eddy viscosity effects. This submodel was used to generate the typical lake circulation patterns for different steady state wind and ice conditions which are required for the long-term pollutant simulation study by the EPA (TOXIWASP) model. The depth averaged velocities were also used in finite element pollutant and suspended sediment transport models. An upwind finite element formulation was used to obtain a stable solution for the steady state convective transport phenomena.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses u26 Major Papers - Basement, West Bldg. / Call Number: Thesis1986 .I373. Source: Dissertation Abstracts International, Volume: 47-05, Section: B, page: 2084. Thesis (Ph.D.)--University of Windsor (Canada), 1986.