Title
Estimating and localizing the algebraic and total numerical errors using flux reconstructions.
Abstract
This paper presents a methodology for computing upper and lower bounds for both the algebraic and total errors in the context of the conforming finite element discretization of the Poisson model problem and an arbitrary iterative algebraic solver. The derived bounds do not contain any unspecified constants and allow estimating the local distribution of both errors over the computational domain. Combining these bounds, we also obtain guaranteed upper and lower bounds on the discretization error. This allows to propose novel mathematically justified stopping criteria for iterative algebraic solvers ensuring that the algebraic error will lie below the discretization one. Our upper algebraic and total error bounds are based on locally reconstructed fluxes in \({\mathbf {H}}(\mathrm{div},\varOmega )\), whereas the lower algebraic and total error bounds rely on locally constructed \(H^1_0(\varOmega )\)-liftings of the algebraic and total residuals. We prove global and local efficiency of the upper bound on the total error and its robustness with respect to the approximation polynomial degree. Relationships to the previously published estimates on the algebraic error are discussed. Theoretical results are illustrated on numerical experiments for higher-order finite element approximations and the preconditioned conjugate gradient method. They in particular witness that the proposed methodology yields a tight estimate on the local distribution of the algebraic and total errors over the computational domain and illustrate the associated cost.
Year
DOI
Venue
2018
10.1007/s00211-017-0915-5
Numerische Mathematik
Keywords
Field
DocType
Numerical solution of partial differential equations, Finite element method, A posteriori error estimation, Algebraic error, Discretization error, Stopping criteria, Spatial distribution of the error, 65N15, 65N30, 76M10, 65N22, 65F10
Conjugate gradient method,Discretization,Singular point of an algebraic variety,Mathematical optimization,Algebraic number,Mathematical analysis,Upper and lower bounds,Numerical partial differential equations,Algebraic function,Real algebraic geometry,Mathematics
Journal
Volume
Issue
ISSN
138
3
0029-599X
Citations 
PageRank 
References 
2
0.37
22
Authors
3
Name
Order
Citations
PageRank
J. Papez120.37
Zdeněk Strakoš25410.51
Martin Vohralík3425.89