Author(s): Il Won Seo; Eun Woo Son
Linked Author(s): Il Won Seo
Keywords: Shear flow dispersion; 1D dispersion model; Longitudinal advection; Transverse diffusion; Longitudinal dispersion coefficient; Sequential mixing model
Abstract: To investigate the one-dimensional advection-diffusion process and to develop a new method for determining dispersion coefficient the sequential mixing model is proposed based on the main concept that the longitudinal advection and the transverse diffusion are separate and additive after reaching the balanced state, and the lateral distribution of the longitudinal velocity plays an important role on the mixing process. From the comparison between the model and the one dimensional advection-diffusion model, the concentration profile from the newly-proposed model showed good agreement with the analytical solution following Gaussian distribution. From fitting the analytical Gaussian solution to the concentration profile of the model, the longitudinal dispersion coefficient observed to have linear relationships with time for mixing mt and the square of the intensity of the velocity deviation, which coincides with Fischer ’s result. Using a variety of the velocity distributions the dimensionless integral can be deduced to be a power function of the width-to-depth ratio of the channel.
Year: 2005