Title
Local-global multiscale model reduction for flows in high-contrast heterogeneous media
Abstract
In this paper, we study model reduction for multiscale problems in heterogeneous high-contrast media. Our objective is to combine local model reduction techniques that are based on recently introduced spectral multiscale finite element methods (see [19]) with global model reduction methods such as balanced truncation approaches implemented on a coarse grid. Local multiscale methods considered in this paper use special eigenvalue problems in a local domain to systematically identify important features of the solution. In particular, our local approaches are capable of homogenizing localized features and representing them with one basis function per coarse node that are used in constructing a weight function for the local eigenvalue problem. Global model reduction based on balanced truncation methods is used to identify important global coarse-scale modes. This provides a substantial CPU savings as Lyapunov equations are solved for the coarse system. Typical local multiscale methods are designed to find an approximation of the solution for any given coarse-level inputs. In many practical applications, a goal is to find a reduced basis when the input space belongs to a smaller dimensional subspace of coarse-level inputs. The proposed approaches provide efficient model reduction tools in this direction. Our numerical results show that, only with a careful choice of the number of degrees of freedom for local multiscale spaces and global modes, one can achieve a balanced and optimal result.
Year
DOI
Venue
2012
10.1016/j.jcp.2012.07.032
J. Comput. Physics
Keywords
Field
DocType
local eigenvalue problem,efficient model reduction tool,local approach,local model reduction technique,coarse-level input,local-global multiscale model reduction,typical local multiscale method,local multiscale space,global model reduction,local multiscale method,high-contrast heterogeneous media,local domain,finite element
Lyapunov function,Mathematical optimization,Weight function,Subspace topology,Finite element method,Basis function,Balanced truncation,Mathematics,Eigenvalues and eigenvectors,Grid
Journal
Volume
Issue
ISSN
231
24
0021-9991
Citations 
PageRank 
References 
17
1.08
18
Authors
3
Name
Order
Citations
PageRank
Yalchin Efendiev158167.04
Juan Galvis234926.24
Eduardo Gildin3304.48