A high-order discretization of nonlinear poroelasticity
Michele Botti, Daniele A. Di Pietro, Pierre Sochala
TL;DR
The paper addresses nonlinear poroelasticity in the quasi‑static Biot framework, coupling a nonlinear elasticity model with Darcy flow through $-oldsymbol{ abla}oldsymbol{oldsymbol{ abla}}oldsymbol{ au}+oldsymbol{ abla}p=oldsymbol{f}$ and $C_0rac{dp}{dt}+oldsymbol{ abla}oldsymbol{ abla}oldsymbol{u}-oldsymbol{ abla}oldsymbol{ abla}oldsymbol{ abla}p=oldsymbol{g}$, with the Biot coefficient set to $oldsymbol{ abla}=1$ for simplicity. It proposes a nonconforming high‑order discretization that uses the Hybrid High‑Order method for nonlinear elasticity and the Symmetric Weighted Interior Penalty discontinuous Galerkin scheme for Darcy flow, applicable in both 2D and 3D on polyhedral meshes. The main contributions are an inf‑sup stable discretization on general meshes, compatibility with arbitrary approximation orders, and the ability to statically condense a large subset of unknowns in linearized steps, along with robustness to vanishing storage $C_0$ and variable permeability. Theoretical results include stability, well‑posedness, and optimal convergence rates, complemented by numerical tests on Cartesian and Voronoi meshes that corroborate the predicted accuracy and demonstrate robustness on nonmatching interfaces. These advances offer a practical and provably reliable tool for simulating nonlinear poroelastic effects in heterogeneous geophysical settings.
Abstract
In this work we construct and analyze a nonconforming high-order discretization method for the quasi-static single-phase nonlinear poroelasticity problem describing Darcean flow in a deformable porous medium saturated by a slightly compressible fluid. The nonlinear elasticity operator is discretized using a Hybrid High-Order method, while the Darcy operator relies on a Symmetric Weighted Interior Penalty discontinuous Galerkin scheme. The method is valid in two and three space dimensions, delivers an inf-sup stable discretization on general meshes including polyhedral elements and nonmatching interfaces, supports arbitrary approximation orders, and has a reduced cost thanks to the possibility of statically condensing a large subset of the unknowns for linearized versions of the problem. Moreover, the proposed construction can handle both nonzero and vanishing specific storage coefficients.
