In order to represent the wide variety of transport pathways which you may wish to simulate, GoldSim provides five different pathway element types, which can be used interchangeably in a model:
Cell pathways act as mixing cells. Within a
Cell, all species
mass is assumed to be instantaneously and completely mixed and equilibrated
among all of the Cell's media. Solubility constraints can be imposed within Cell
pathways. When multiple Cells are linked together, the behavior of the Cell
network is mathematically identical to a network of finite difference nodes
describing a coupled system of differential equations.
Aquifer pathways are used to represent features that
essentially behave as fluid conduits or stream tubes. An Aquifer pathway
actually performs its computations by creating a temporary set of linked Cell
elements during the simulation, which are subsequently removed at the end of the
simulation. They can be applied to a broad range of advectively-dominated mass
transport systems involving one-dimensional advection, longitudinal dispersion,
diffusion, retardation, decay and ingrowth.
Pipe pathways are also used to represent features
that essentially behave as fluid conduits or stream tubes. Pipe pathways
use a Laplace
transform approach to provide analytical solutions to a broad range of
advectively-dominated mass transport systems. Because they can represent
processes such as matrix diffusion, they are particularly applicable to modeling
transport through fractured rock masses.
External pathways provide a mechanism by
which external program modules for mass transport (e.g., analytical, finite
element or finite difference transport models) can be directly integrated into
GoldSim. The modules are linked into GoldSim as DLLs (Dynamic Link
Libraries) at run time.
Network pathways provide a computationally
efficient way to simulate large, complex networks of one-dimensional "pipes" in
order to describe mass transport through fractured rock systems. Network
pathways require specification of a separate fracture network, which
typically would be generated by a discrete fracture network generation and flow
simulation code. The fracture network can be very large (100,000 pipes or
more), allowing complex and realistic fracture systems to be simulated.
Network pathways are only available in the RT Module.
Learn more about: