The volumetric mixture source can be applied to one or more fluid domains, and you can specify the volumetric mixture source in terms of the total mass of each species or in terms of the concentration of each species. You can also define a species that is constant throughout space, varies spatially according to mapped data, or varies according to the values specified by a user subroutine. You might want to define species behavior with a user subroutine to simulate drug species decay in a variety of ways, including decay as a function of time and space or decay as a function of overall mass fraction. | ||||||