Simulation of Transport Phenomena in Shallow Aquatic Environment

Abstract

In the framework of the present study, 2D and 3D finite-difference procedures have been developed and applied with regard to flow, heat, and contaminant transport in the marine environment, where a shallow aquatic environment can be assumed. The common characteristic of such a type of environment is that the water depth is much smaller than a typical length in the horizontal direction. Conditions of this environment allow 2D or shallow water 3D numerical models to be applied instead of a more expensive and time consuming full 3D solution. Such an approach is almost obtained without loss of accuracy. By reference to a practical case of a wind dominated environment, the requirements and possible use of the 2D or 3D numerical codes are identified and analyzed. It is shown that the applicability of the 2D model mainly depends on the wind direction. Considerations are made with regard to recirculation of thermal effluent into the inlet of a power station. It is shown that, even in an extremely complicated geometry of the simulated domain, the 2D and 3D simulations can provide the same order of magnitude of results for some wind directions, particularly in the case of wind blowing parallel to the shoreline. On the other hand, for a wind direction nearly perpendicular to the shoreline, the 2D model produces unreliable or simply nonphysical results, whereas the 3D model provides reliable results. These conjectures are of great practical importance because most of the previous thermal effluent studies have been carried out by using the 2D modeling. It is considered that the performance of the 2D and shallow water 3D simulations provide an adequate description and understanding of basic transport phenomena in the simulated domain