|Authors||J. B. Haga, H. P. Langtangen and H. Osnes|
|Title||A Parallel Block Preconditioner for Large Scale Poroelasticity With Highly Heterogeneous Material Parameters|
|Afilliation||Scientific Computing, Center for Biomedical Computing (SFF), Scientific Computing, Scientific Computing|
|Publication Type||Journal Article|
|Year of Publication||2012|
Large-scale simulations of coupled flow in deformable porous media require iterative methods for solving the systems of linear algebraic equations. Construction of efficient iterative methods is particularly challenging in problems with large jumps in material properties, which is often the case in realistic geological applications, such as basin evolution at regional scales. The success of iterative methods for such problems depends strongly on finding effective preconditioners with good parallel scaling properties, which is the topic of the present paper. We present a parallel preconditioner for Biot's equations of coupled elasticity and fluid flow in porous media. The preconditioner is based on an approximation of the exact inverse of the two-by-two block system arising from a finite element discretisation. The approximation relies on a highly scalable approximation of the global Schur complement of the coefficient matrix, combined with generally available state-of-the-art multilevel preconditioners for the individual blocks. This preconditioner is shown to be robust on problems with highly heterogeneous material parameters. We investigate the weak and strong parallel scaling of this preconditioner on up to 512 processors, and demonstrate its ability on a realistic basin-scale problem in poroelasticity with over 8 million tetrahedral elements.