Quasi 3D Refined Simulation of Flow and Pollutant Transport in The Mississippi River near The Rock Lake

This paper reports a quasi 3D numerical simulation in a curved river reach of the Mississippi River near The Rock Lake, USA, aiming to develop a numerical tool for modeling turbulent flows and pollutant transport in complex natural waters. The recently built depth-averaged two-equation turbulence ω ~ ~ - k model, together with e ~ ~ - k and w k ~ ~ - models, were used to close non-simplified quasi 3D hydrodynamic fundamental governing equations. The discretized equations were solved by advanced multi-grid iterative method under non-orthogonal body-fitted coarse and fine two-levels' grids with collocated variable arrangement. Except for steady flow and transport computation, the processes of contaminant inpouring and plume development, caused by the side-discharge from a tribytary, also have been investigated numerically. The used three closure approaches are suitable for modeling strong mixing turbulence. The established ω ~ ~ - k model with higher order of magnitude of transported variable ω ~ provides a possibility to elevate the computational precision. Based on the developed hydrodynamic model, a CFD (Computational Fluid Dynamics ) software, namely Q3drm1.0 , was developed. This tool focuses on the refined simulations of the steady and unsteady problems of flow and temperature/contaminant transports in complicated computational domains with a strong ability to deal with different types of discharges: side-discharge, point- source/point-sink, and area-source discharge from the slope along bank. In this paper, only the study of side-discharge is presented.