Calculation Of A Forced Plume In A CoastalArea By A Three-Dimensional K-c-E Model

Abstract

The purpose of this study is to investigate the diffusion mechanism of thermal water, behaving a forced plume, discharged from a power plant with in-situ observation and numerical approach. A three-dimensional k-e-E model was developed to predict the diffusion process and to apply in practical uses. The field observation was conducted to investigate the dispersion process of a forced plume in a sea where a semidiurnal tidal current was dominant and a large amount of thermal water ~50m /s was discharged from a thermal power plant with multiple pipes. The horizontal eddy diffusivity in the area where each plume overlapped and formed one large plume was well estimated by the width of a plume*. The observed vertical eddy viscosity at this area was ~ 1 x 10 cm /s which was in good agreement with the result calculated by the numerical model. The results of the calculations also showed that the direction of the plume and the horizontal distribution of the velocity and the temperature were in good accordance with the observation results, however there was a little discrepancy between both results concerning the diffusion width of a plume at the surface.