GGU-CONTAM-RW: "Soil properties" menu item
After going to this menu item, a system-specific dialog box opens allowing input of the soil properties. The steady-state property neff imported from the GGU-2D-SSFLOW program can no longer be amended here
In the example above, one soil has been defined for the system (groundwater modelling with GGU-2D-SSFLOW). Enter the soil parameters relevant to contaminant transport in the input boxes:
"Info"
This item provides information on the meaning of the parameters and the units used by them. Please ensure that you always use the same length and time units as those you applied to the permeability in the steady-state modelling in GGU-2D-SSFLOW. You can define the mass dimension at will; you must, however, use the same dimension for all parameters. This also applies to the subsequent definition of initial concentrations and concentration sources."alph_l"
Enter the value of the longitudinal dispersivity alph_l. This is a function of grain size and varies between a few centimetres (laboratory tests in sand) and over 100 metres (jointed rocks)."alph_t"
The transversal dispersivity alph_t is generally a magnitude smaller than the longitudinal. In field tests, ratios around 0.01 were determined. Values of up to 0.3 are given in the literature."Dm"
Enter the value of the diffusion coefficient Dm. This value only influences contaminant distribution at very low flow velocities. For water at 10°C, this value is 10-9 m/s²."Sorp"
Enter the value of the sorption constant sorp. The sorption constant is dimensionless and is the product of grain density and the adsorption coefficient."lambda"
Enter the value of the decay constant lambda.