Numerical Study of Pollutant Transport in Breaking Random Waves on Mild Slope Zone

Pollutant transport in breaking random water waves on mild slope zone was studied by using the numerical models. In the models, propagation of random water waves was modeled by parabolic mild slope equation, breaking random wave induced currents were modeled by shallow water equation, and pollutant transport in surf zone was modeled by pollutant motion model. The numerical results indicated that the breaking wave induced long-shore current was a main hydrodynamic factor for pollutant transport in surf zone. Moreover, the pollutant transported more quickly as the emission location was closer to wave breaking line, and the pollutant near wave breaking line transported more quickly with the increase of the incident wave height and offshore plane steepness. Furthermore, the wave period had more obvious influence on pollutant transport when wave breaking was governed by wave steepness rather than by water depth in surf zone. The pollutant transport in random breaking waves showed the same tendency as that in regular breaking waves.