Comet 3
Comet 3 is used to model unconventional recovery from dual or triple
porosity reservoirs.  In the traditional dual porosity mode it models fluid
flow to the well through natural fracture networks and desorbtion from the
matrix into the fractures.  In triple porosity mode it handles fluid flow
through both the natural fractures and matrix as well as desorbtion.  The
model is an industry standard used for both coal gas and shale gas
problems