Two-dimensional numerical model for thermal pollution of single-point sources in rivers at different discharge depths

Abstract EN

A two-dimensional numerical model has been developed depending on finite-difference techniques to simulate the temperature and flow patterns resulting from unsteady continuous thermal discharge applied to river stream as a single-point source at different thermal discharge locations.

In this study three cases of thermal discharge to the river reach stream are adopted, first case is at the water surface of the river, second case is as submerged outfall lying at 0.42 from the river depth, while the third case is a submerged outfall at 0.83 from the river depth.

The latest discharge case is considered the basic contribution in this study.

The governing equations in the present model are momentum conservation equation and thermal-energy equation.

The turbulent dynamic viscosity and diffusion coefficient were calculated by using the modified (k - ε) turbulence model.

The partial differential equations were converted into finite difference form using (ADI) finite difference technique with application the up winding scheme and then the set of the linear algebraic equations were solved by Gauss-Seidel Point-by-Point Method.

(Shati, 2007) The results of the system were verified by using a numerical model presented by Al-Chalabi, M.A (1993).

A sensitivity analysis was carried out to study the effect of variations of different parameters on the temperature distribution resulting from the application of the model at and beneath the water surface.