Description: geomechanical model for C02 sequestration
|(undirected graph drawing)|
|number of rows||923,136|
|number of columns||923,136|
|structural full rank?||yes|
|# of blocks from dmperm||14,425|
|# strongly connected comp.||14,425|
|explicit zero entries||631,668|
|nonzero pattern symmetry||symmetric|
|numeric value symmetry||symmetric|
|author||C. Janna, M. Ferronato|
Authors: Carlo Janna and Massimiliano Ferronato Symmetric Positive Definite Matrix # equations: 923136 # non-zeroes: 41005206 Problem description: Geomechanical problem The matrix Emilia_923 is obtained from a structural problem discretizing a gas reservoir with tetrahedral Finite Elements. Due to the complex geometry of the geological formation it was not possible to obtain a computational grid characterized by regularly shaped elements. The problem arises from a 3D discretization with three displacement unknowns associated to each node of the grid. Some further information may be found in the following papers: 1) M. Ferronato, G. Gambolati, C. Janna, P. Teatini. "Geomechanical issues of anthropogenic CO2 sequestration in exploited gas fields", Energy Conversion and Management, 51, pp. 1918-1928, 2010. 2) C. Janna, M. Ferronato. "Adaptive pattern research for block FSAI preconditionig". SIAM Journal on Scientific Computing, to appear.
|nnz(chol(P*(A+A'+s*I)*P')) with AMD||5,317,434,978|
|Cholesky flop count||1.3e+14|
|nnz(L+U), no partial pivoting, with AMD||10,633,946,820|
|nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD||6,960,196,599|
|nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD||12,298,145,622|
Note that all matrix statistics (except nonzero pattern symmetry) exclude the 631668 explicit zero entries.
For a description of the statistics displayed above, click here.
Maintained by Tim Davis, last updated 12-Mar-2014.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.