Defining Species

Species GoldSim provides a specialized element for defining the contaminant species in a simulation. The Species element is located in the Material Container, which is automatically created in the Model Root whenever you create a new file with the Contaminant Transport Module. This element can be moved, but it cannot be deleted.

The Species element is used to add, delete, and edit species. Double-clicking on the Species element brings up the following dialog:

Because the RT Module allows decay chains (daughter products) to be simulated (and to support this, allows you to link to an extensive database of radionuclide decay data), the Species dialog is slightly different depending on whether you are using the RT Module or the CT Module. The screen above is from the RT Module. If you are using the CT Module, some of the fields will not be available.

Species are added (and deleted) using the Add…and Delete… buttons. (If you are using the RT Module, you also have access to a large database of radionuclide species that can be selected to be included in the model).

Double-clicking on an existing species in the list, or adding a new species displays the Species editing dialog:

The fundamental properties of the species are defined in this window, including the rate at which the species decays (entered as either a half-life or a first-order decay rate), and whether it is part of a decay chain. Although GoldSim requires a first-order decay rate, by making the decay rate a function of the concentration of other species, or of other model parameters (e.g., temperature), nearly any complex reaction can be represented.

Note: Decay chains can only be specified in the RT Module.