Open Access Open Access  Restricted Access Subscription Access

Numerical Simulation of the Contaminant Release Through the Sediment-Overlying Water Interface

S. ZHENG, J. GUO, D. WANG

Abstract


On the condition that the overlying water flow does not lead to sediment suspension, numerical researches are carried out for the contaminant release mechanism through the sediment-overlying water interface. The overlying water flow is calculated using the k −e turbulence model. The sediment is regarded as isotropic homogeneous porous medium, therefore the seepage field in the porous sediment layer is obtained by solving Darcy’s equations. Several two dimensional coupled steady flow of the overlying water and the pore water in the sediment are calculated. Based on the flow fields obtained, the unsteady contaminant solute transportation process in the sediment and the overlying water is numerically simulated, as the shapes of the sediment-overlying water interface are flat or periodic triangular respectively. Numerical results show that the exchange of the pore water and the overlying water is an important factor which decides the release flux of the contaminant from the sediment to the overlying water. The non-uniform pressure distribution along the sediment-overlying water interface may induce the seepage of the pore water in the sediment and through the sediment-overlying water interface, which may increase the release flux of the contaminant from the sediment to the overlying water

Full Text:

PDF