Mathematically, if A decays to B, GoldSim computes the rate of change of mass (at a particular location) as follows:
dMA/dt = - MA DA
dMB/dt = MA DA RBA WB / WA
where:
MA = the mass of
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). A (mass);
dMA/dt = the
rate of change of species A (mass/time);
dMB/dt = the rate of
change of species B (mass/time);
DA = decay rate of species A
(1/time);
RBA = stoichiometry (moles B produced per moles A
decayed);
WA = molecular (or atomic) weight of species A;
and
WB = molecular (or atomic) weight of species B.
Note: The accuracy of the decay algorithm in GoldSim is a function of the solution precision setting (high, medium or low) defined in the Contaminant Transport tab of the Options dialog (accessed from the main menu by selecting Model | Options).
- Deactivating Decay
- Defining Decay Rates that Vary by Location
- Defining Spatially Variable Decay Rates
- Defining Species Decay Properties
- How GoldSim Simulates Decay
- Modeling Complex Chemical Reactions
- Simulating Isotopes of the Same Element
- Simulating Radioactive Species
- The Species and Elements Array Label Sets