Defining Fluids

The editing dialog for a Fluid is shown below:

The dialog is identical to that of the Reference Fluid A special type of Fluid element that provides a basis for defining partition coefficients between media for the various species in the model (i.e., the ratio of the species’ concentration in the medium to its concentration in the Reference Fluid at equilibrium). with one exception: you have a choice of either defining solubilities or partition coefficients The ratio of the species’ concentration in a medium to its concentration in the Reference Fluid at equilibrium. Partition coefficients are inputs to Solid and Fluid elements. (for the Reference Fluid you can only specify solubilities).

In most cases, you will want to define partition coefficients (rather than solubilities) for the Fluid (and this is the default). Partition coefficients determine how species The chemical (or non-chemical, such as bacterial or viral) constituents that are stored and transported through an environmental system in a contaminant transport model. In GoldSim, the Species element defines all of the contaminant species being simulated (and their properties). partition between the Fluid and the Reference Fluid. By definition, the solubility in the Reference Fluid, along with the partition coefficients for the Fluid relative to the Reference Fluid, automatically determine the saturation concentration in the Fluid when the solubility limit for a system containing the Fluid is reached.

In some cases, you may want to create new Fluids in which you define solubilities for the Fluids. In this case, GoldSim automatically computes the partition coefficients for the Fluid with respect to the Reference Fluid. (By definition, the partition coefficient for a species is simply the ratio of the solubility in the Fluid to the solubility in the Reference Fluid).