26 citations · 95 across the 9 of their papers we have counts for
11 papers
Space-time block preconditioning for incompressible flow
Federico Danieli, Ben S. Southworth, Andrew J. Wathen
Parallel-in-time methods have become increasingly popular in the simulation of time-dependent numerical PDEs, allowing for the efficient use of additional MPI processes when spatia…
Multipreconditioning with application to two-phase incompressible Navier-Stokes flow
Niall Bootland, Andrew Wathen
We consider the use of multipreconditioning to solve linear systems when more than one preconditioner is available but the optimal choice is not known. In particular, we consider a…
Sparse inversion for derivative of log determinant
Shengxin Zhu, Andrew J Wathen
Algorithms for Gaussian process, marginal likelihood methods or restricted maximum likelihood methods often require derivatives of log determinant terms. These log determinants are…
A constrained pressure-temperature residual (CPTR) method for non-isothermal multiphase flow in porous media
Thomas Roy, Tom B Jönsthövel, Christopher Lemon +1
For both isothermal and thermal petroleum reservoir simulation, the Constrained Pressure Residual (CPR) method is the industry-standard preconditioner. This method is a two-stage p…
A block preconditioner for non-isothermal flow in porous media
Thomas Roy, Tom B. Jönsthövel, Christopher Lemon +1
In petroleum reservoir simulation, the industry standard preconditioner, the constrained pressure residual method (CPR), is a two-stage process which involves solving a restricted…
Essential formulae for restricted maximum likelihood and its derivatives associated with the linear mixed models
Shengxin Zhu, Andrew J Wathen
The restricted maximum likelihood method enhances popularity of maximum likelihood methods for variance component analysis on large scale unbalanced data. As the high throughput bi…
Preconditioners for Two-Phase Incompressible Navier-Stokes Flow
Niall Bootland, Alistair Bentley, Christopher Kees +1
We consider iterative methods for solving the linearised Navier-Stokes equations arising from two-phase flow problems and the efficient preconditioning of such systems when using m…
Preconditioning for boundary control problems in incompressible fluid dynamics
Gennadij Heidel, Andy Wathen
PDE-constrained optimization is a field of numerical analysis that combines the theory of PDEs, nonlinear optimization and numerical linear algebra. Optimization problems of this k…
Three-field block-preconditioners for models of coupled magma/mantle dynamics
Sander Rhebergen, Garth N. Wells, Andrew J. Wathen +1
For a prescribed porosity, the coupled magma/mantle flow equations can be formulated as a two-field system of equations with velocity and pressure as unknowns. Previous work has sh…
Analysis of block-preconditioners for models of coupled magma/mantle dynamics
Sander Rhebergen, Garth N. Wells, Richard F. Katz +1
This article considers the iterative solution of a finite element discretisation of the magma dynamics equations. In simplified form, the magma dynamics equations share some featur…
Stability and preconditioning for a hybrid approximation on the sphere
Q. T. Le Gia, Ian H. Sloan, Andrew J. Wathen
This paper proposes a new preconditioning scheme for a linear system with a saddle-point structure arising from a hybrid approximation scheme on the sphere, an approximation scheme…