An Introduction to Multi-Point Flux (MPFA) and Stress (MPSA) Finite Volume Methods for Thermo-Poroelasticity

We give a unified introduction to the MPFA- and MPSA-type finite volume methods for Darcy flow and poro-elasticity, applicable to general polyhedral grids. This leads to a more systematic perspective of these methods than has been exposed in previous texts, and we therefore refer to this discretization family as the MPxA methods. We apply this MPxA framework to also define a consistent finite-volume discretization of thermo-poro-elasticity. In order to make the exposition accessible to a wide audience, we avoid much of the technical notation which is used in the research literature, and compensate for this by an expanded summary and literature review of the main properties of the MPxA methods. We close the chapter by a section containing applications to problems with complex geometries and non-linear physics.