Environmental Sciences Seminar: Il-Won Seo
- Modelling Pollutant Transport in Streams Using Particle Tracking
- Il-Won Seo, PHD, Seoul National University, Department of Civil Engineering
- Dr. Seo, currently a Professor at the Seoul National University in Seoul, S. Korea, is spending the fall semester on sabbatical leave at CCNY.
- In order to study two- dimensional pollutant mixing in open channel flows we developed a non-Fickian particle dispersion model. The proposed model represents shear dispersion using step-by-step arithmetic calculations, which consist of horizontal transport and vertical mixing steps, instead of using Fick’s law. In these sequential calculations, the model directly applies the effect of vertical variations of both longitudinal and transverse velocities, whereas the Fickian dispersion model incorporates the effect of shear flow in the dispersion
- coefficients. Furthermore, to avoid the numerical diffusion errors induced by the grid tracking method of previously developed non-Fickian dispersion models, this model adopts the particle tracking technique to trace each particle. The simulation results for straight channels show that the proposed model reproduces the anomalous mixing, which shows a non-linear increase of variance with time and a large skewness coefficient in the initial period. However, in
- the Taylor period, the variance and skewness of the concentration curves approach the Fickian mixing. The simulation results in the meandering channel reveal that the proposed model adequately reproduces the skewed concentration-time curves of the experimental results whereas the Fickian dispersion model, CTM-2D, generates symmetrical curves. Further comparison between the simulation results and the tracer test results conducted in the Seom River shows that the proposed model properly reproduces two-dimensional mixing without adopting Fick’s law.
October 22, 2018
12:30 PM — 1:30 PM
Advanced Science Research Center, GC/CUNY
85 St. Nicholas Terrace
5th Floor Data Visualization Room