Contaminant and sediment transport by advection and diffusion 217
Run the simulations, compare the results and comment on the changes
observed regarding the spreading of the contaminant plume.
Example 8.4
This application involves the simulation of a contaminant advection and diffusion using a Lagrangian particle-tracking method for
the Thermaikos Gulf. The bathymetry, velocity field and location
of the contaminant source are the same to the ones in Example 8.2.
The  source is simulated by 5000 particles introduced at time t = 0.
The simulation was conducted for a period of 288 time steps (2 days)
and the results are illustrated in Figure 8.6. By comparing the results
of the particle-tracking method (Figure 8.6) and those from the solution of the advection–diffusion equation (Figure 8.3), it can be seen
that the Eulerian method shows a balance between advective and diffusive transport while the Lagrangian method emphasizes the diffusive effects. However, overall there was agreement between the two
methods.
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Figure 8.6 Mass transport in Thermaikos Gulf using the particle-tracking method.