Decay

Many processes can be approximated by a simple first-order decay, such as die-off of E. Coli due to exposure to light, decay of the activity of radioactive substances or estimating the age of water bodies.

First order decay of a component is generally described by

(5.1)   

or

(5.2)   

where c is the specific concentration, c₀ is the initial concentration and k is the decay factor. In the model the decay term is added to the general transport equation.

The decay is specified individually for each component.

Data