Abstract
Analyses of flow and pollutant dispersion based on computational fluid dynamics (CFD) have attracted considerable attention. Thus, this study developed a turbulent diffusivity limiter using the travel time for predicting point-source pollutant dispersion based on CFD analysis using the k-ε turbulence model and Eulerian concentration transport equations. In this method, the travel time is numerically predicted employing a virtual tracer called the radioactive tracer. Then, the method was applied to predict point-source pollutant dispersion in a two-dimensional uniform turbulent flow. Results showed that the method could reproduce the theoretically predicted increase in the plume width proportional to the travel time during the early stage of dispersion. Moreover, the turbulent diffusivity and plume width at the early and final stages of dispersion could be controlled by adjusting the combination of three model parameters in the turbulent diffusivity limiter.
